# Exploring Asymmetric Roles in Mixed-Ability Gaming

David Gonçalves  LASIGE, Faculdade de Ciências, Universidade de
LisboaLisboaPortugal<EMAIL_ADDRESS>,  André Rodrigues  LASIGE,
Faculdade de Ciências, Universidade de LisboaLisboaPortugal
<EMAIL_ADDRESS>,  Mike L. Richardson  Department of Psychology,
University of BathBathUnited Kingdom<EMAIL_ADDRESS>,  Alexandra A. de Sousa
Centre for Health and Cognition, Bath Spa UniversityBathUnited Kingdom
<EMAIL_ADDRESS>,  Michael J. Proulx  Department of Psychology,
University of BathBathUnited Kingdom<EMAIL_ADDRESS>and  Tiago Guerreiro
LASIGE, Faculdade de Ciências, Universidade de LisboaLisboaPortugal
<EMAIL_ADDRESS>
(2021)

###### Abstract.

The landscape of digital games is segregated by player ability. For example,
sighted players have a multitude of highly visual games at their disposal,
while blind players may choose from a variety of audio games. Attempts at
improving cross-ability access to any of those are often limited in the
experience they provide, or disregard multiplayer experiences. We explore
ability-based asymmetric roles as a design approach to create engaging and
challenging mixed-ability play. Our team designed and developed two
collaborative testbed games exploring asymmetric interdependent roles. In a
remote study with 13 mixed-visual-ability pairs we assessed how roles affected
perceptions of engagement, competence, and autonomy, using a mixed-methods
approach. The games provided an engaging and challenging experience, in which
differences in visual ability were not limiting. Our results underline how
experiences unequal by design can give rise to an equitable joint experience.

game accessibility, visual impairment, mixed-ability, social gaming, inclusion

††journalyear: 2021††copyright: acmcopyright††conference: CHI Conference on
Human Factors in Computing Systems; May 8–13, 2021; Yokohama,
Japan††booktitle: CHI Conference on Human Factors in Computing Systems (CHI
’21), May 8–13, 2021, Yokohama, Japan††price: 15.00††doi:
10.1145/3411764.3445494††isbn: 978-1-4503-8096-6/21/05††ccs: Human-centered
computing Accessibility††ccs: Human-centered computing Interaction design

Figure 1. Screenshot details presenting the roles in the games: Pilot (A) and
Engineer (C) in Rescue: Under Pressure. Pilot (B) and Engineer (D) in Rescue:
Mayday

Sections A, B, C and D represent the pixel-art graphics when playing each of
the four different game roles. Section A (Pilot in SUB) shows a submarine,
seen from the side, close to a wall of rocks. A mechanical claw protruding
from the submarine’s hatch is aiming towards a colored rock which is actually
a mineral. The central area is lit by a spotlight around the submarine and
everything outside of that is black. Section B (Pilot in AIR) shows an
airplane viewed from above, on the sky. Particles are emitted from the tail of
the plane, which suggest it is moving. A strip at the bottom represents the
available and selected radio frequency. Section C (Engineer in SUB) shows a
system with a speaker and two monitors, one of them resembling a sonar/radar
display. Section D (Engineer in AIR) shows a system with several buttons and
monitors. On a large monitor, colored shapes are marked, among which helipad
symbols, and minimal representations of clouds and airplanes are discerned.
Each smaller monitor shows coordinates of a rescue task and a symbol that
indicates whether it is a fire or a person in danger. One of these small
monitors has nothing typed and it would remain empty until the Pilot answered
a new distress call. Below these small monitors, there are three buttons. The
first button has the symbol of a flame, the second of a human face and the
third of a trash bin. There’s also a small circular display with a blue
pointer, which is actually the water tank meter.

##  1\. Introduction

Games usually target a stereotypical player, with a defined set of abilities.
For example, most game designs assume players can press various keys at the
same time and have the ability to process visual stimuli. This makes most
games inaccessible for people who have sensory, motor and/or cognitive
disabilities.

People with disabilities are used to playing games that are exclusively
designed for them (Andrade et al., 2019; Yuan et al., 2011; Archambault et
al., 2007). Similar to mainstream games, the specific targeting does not
consider the interplay between abilities and/or preferences. The lack of
intersection leads to isolated communities based on abilities (Gonçalves et
al., 2020). For example, audio games111 https://audiogames.net/ (Last visited
on August 26th, 2020) are almost exclusively played by people with visual
impairments. These games are typically designed disregarding the stereotypical
needs of sighted people (i.e. most audio games don’t have visuals or are not
considered appealing).

Despite the availability of a wide variety of accessible games, mixed-ability
gaming contexts remain a challenge. Either games cannot be independently
played by people with disabilities (Yuan et al., 2011; Porter and Kientz,
2013), or games that account for their abilities do not generate enough
interest from others with different sets of abilities (Gonçalves et al., 2020;
Andrade et al., 2019). In gaming, we are at a point where it is important to
find ways to ensure inclusive experiences, ways that envision mixed-ability
interaction as an opportunity, rather than a limitation (Esenkaya et al.,
2020). In particular, ways to design equally engaging and challenging gaming
experiences that overcome differences in players’ abilities, stigma and
promote social inclusion (Holloway, 2019). In our work we explored the design
of asymmetric roles in pursuing such experiences.

Asymmetry, in a multiplayer gaming context, means players are presented with
distinct gameplays, which can differ at different levels (e.g. character
abilities, goals, information) (Fullerton, 2008). Research has explored
asymmetry before and it has been shown to improve connectedness, especially
when a tight cooperation is involved through interdependent roles (Harris and
Hancock, 2019).

We explored the design of asymmetric roles with ability-based challenges
entwined in an interdependent collaboration as a strategy to cater for
different abilities. We focused on mixed-visual-ability scenarios, thus one
role did not require vision and was designed around demanding auditory
challenges, while the other focused on visual tasks. Past research has found
how often games that strive to be accessible, do so by simplifying games,
leading players to quickly lose interest (Andrade et al., 2019). Furthermore,
the feeling of unfairness is typically a barrier in mixed-visual-ability
gaming experiences (Gonçalves et al., 2020). As such, a major point in our
approach was to ensure players are challenged on par. We designed two games
following this approach and conducted an exploratory user study with mixed-
visual-ability pairs. We had the following research questions.

  * •

Can asymmetric ability-based roles create engaging experiences for both
players?

  * •

How do interdependent ability-based challenges affect players perceived
competence and autonomy?

Our results show how ability-based experiences designed to be unequal can
result in equitable gaming spaces where differences in abilities are not
limiting. Moreover, the approach showed potential in raising awareness about
different abilities and overcoming stigmas. We aim to encourage new ways of
designing for mixed-ability play and inspire other researchers and game
designers on the path to inclusive gaming.

##  2\. Related Work

Here we give an overview of accessible games for people with visual
impairments, with a special focus on audio games. Next, we inspect mixed-
ability play and asymmetry in gaming by presenting example works from industry
and research.

###  2.1. Accessible games to people with visual impairments

In recent years, the gaming industry has made significant efforts towards more
accessible gaming. Notably, the 2015 PS4 update included many accessibility
features such as text-to-speech and resizable fonts. Microsoft debuted Xbox
Copilot222Copilot on Xbox One. https://beta.support.xbox.com/help/account-
profile/accessibility/copilot (Last visited on September 16th, 2020) in 2017,
an ease of access feature that links two controllers to act as one, enabling
co-play and player assistance. Also, following the release of the Xbox
Adaptive controller in 2018, specially designed for players with motor
impairments, Microsoft patented the Xbox Braille Controller (Coldewey, 2019)
in 2019, a controller with a built-in Braille display. Game developer company
Ubisoft Entertainment SA provides audio descriptions for the trailers of its
most recent released games (Reparaz, 2020).

However, the adoption of accessibility guidelines is not consistent in
mainstream gaming (Porter and Kientz, 2013). Importantly, most games still
remain unplayable by people with severe visual impairments, since they do not
benefit from visual enhancements (i.e. color and contrast options) and depend
on audio feedback. Past research has explored different strategies to adapt
games that require vision to an accessible audio-based gameplay (Yuan and
Folmer, 2008; Westin, 2004; Smith and Nayar, 2018; Atkinson et al., 2006;
Kirke, 2018; Morelli et al., 2010a; Morelli et al., 2010b). In most cases a
substantial redesign is needed to ensure that the player is able to perceive
the information, determine the correct action, and provide input.

Some games are shown to be successful in this adaptation. Blackbox (Pixel,
2016) is an awarded iOS puzzle game, where all puzzles were rethought to be
accessible through sound and haptics after its initial release. The Last of Us
Part II (Naughty Dog, 2020), a 2020 top-selling game by Naughty Dog, offers
more than 60 accessibility options to players (Staff, 2020). Notably, the game
includes an audio-based reliable rendition of the gameplay that allows someone
to play with no visuals at all (Staff, 2020).

Still, a posteriori adaptation has limitations (Grammenos et al., 2009;
Stephanidis, 2001). One of the potential issues is how the core gameplay may
significantly change (Archambault et al., 2007), namely when it comes to games
that are inherently visual. For example, gameplay in The Witness (Thekla,
Inc., 2016) involves vision-dependent puzzles which would not be convertible
to audio interaction without significantly changing the game mechanics. In
addition, when it comes to multiplayer experiences, this adaptation brings
even more reservations. New strategies are needed to ensure that players with
different abilities are able to play together, and that the experience is
engaging, challenging and fair for all.

People with severe visual impairments are often limited to games that are
designed from the ground up to be played by blind people (audio games) or
games that are compatible with the technologies they use to access devices
(text-based games). These games are not, for the most part, popular among
sighted people and therefore are also exclusive in a different way (Gonçalves
et al., 2020; Andrade et al., 2019). However, they offer a substantial variety
of games that people with visual impairments can play (Andrade et al., 2019;
Urbanek and Güldenpfennig, 2019a).

####  2.1.1. Audio games

Audio games are based on audio-based mechanics and interfaces, relying in the
conveyance of speech, audio cues and sonification techniques like earcons,
sonar and auditory icons (Yuan et al., 2011). They can be played without
visuals and most of them do not have visuals at all. Notably, the web site
audiogames.net presents a list of games that grows frequently with new
installments and updated versions. The evolution of audio games and the
implications for design have been probed before (Urbanek and Güldenpfennig,
2019a, b; Archambault et al., 2007; Yuan et al., 2011; Khaliq and Torre, 2019;
Andrade et al., 2020), highlighting the variety of game mechanics and their
overall popularity among visually impaired gamers.

Andrade et al. (Andrade et al., 2019) established the ability to affect the
game narrative is a critical factor that attracted blind people to gaming. In
fact, many audio and text-based games have a narrative focus. Some also
feature rich complex worlds and give players the opportunity to explore them.
Previous work has inspected alternative navigation systems in games, namely
audio (Atkinson et al., 2006; Matsuo et al., 2016; Sánchez et al., 2010;
Trewin et al., 2008a, b; Westin, 2004; White et al., 2008), text-based (Folmer
et al., 2009) and haptic (Matsuo et al., 2016; Sepchat et al., 2006; Sánchez
et al., 2010; White et al., 2008) interfaces. For instance, in AudioQuake
(Atkinson et al., 2006), an adaptation of the popular Quake (id Software,
1996), researchers use earcons to facilitate in-game interaction. In some
audio-based games there’s an analogy with real-life navigation systems, such
as compass and sonar like features (Andrade et al., 2020; Westin, 2004).
Musicraft (Kirke, 2018) is an audio game inspired by Minecraft, in which the
world is depicted by abstract musical representations.

In contrast to narrative and exploration focused games, action audio games are
typically demanding in terms of dexterity, implying coordination and reaction
challenges. Yuan and Folmer (Yuan and Folmer, 2008) explored the adaptation of
a popular rhythm game, Guitar Hero which, despite being a game about musical
performance, depends on visual interaction. Adaptation leveraged the use of a
glove with small pager motors attached to the tip of each finger, which
transmit the information of the notes that must be played. The adaptation of
exergames for visually impaired people is also explored in previous work
(Morelli et al., 2010b; Morelli et al., 2010a).

###  2.2. Mixed-ability gaming

There are various initiatives to create games accessible for people with
visual impairments. Likewise, others that seek to develop accessible games for
those with motor (Gerling and Buttrick, 2014; Brederode et al., 2005; Hobbs et
al., 2012), hearing (Mascio et al., 2013) and cognitive (Ohring, 2008)
disabilities. Previous work surveyed some of these efforts (Yuan et al.,
2011). However, research and industry tend to depict accessibility as a way of
allowing everyone to experience games, but they typically don’t consider
scenarios in which people experience them together.

Previously, Gonçalves et al. (Gonçalves et al., 2020) approached people with
and without visual impairments, seeking to characterize mixed-visual-ability
gaming experiences. The work outlined two main factors: first, the habits and
gaming experience of people with different visual abilities typically do not
intersect, especially at the extremes of visual ability (i.e. sighted people
play AAA video games, blind people play audio games); second, although these
groups find ways to adapt the games to different needs, gameplay is not
designed to fit these needs and, therefore, the experience is usually
unbalanced and less engaging and/or unfair for someone.

It is also very difficult to adapt certain visual challenges to audio-only
challenges, without losing information or control over the gameplay (Smith and
Nayar, 2018). Smith and Nayar (Smith and Nayar, 2018) developed the RAD, an
auditory display for gamers with visual impairments aiming for equal
accessibility in racing games. Grabski et al. designed Kinaptic (Grabski et
al., 2016), a tag-like game to be played by a blind and a sighted person. The
sighted player interacts through a Kinect and TV, while the blind player
relies on a haptic device, wind simulation and 3D sound. The asymmetric setup
and multimodality proved to be important to ensure players had a fair winning
chance. Inspired by the competitiveness of party games, Imbriani et al.
(Imbriani et al., 2018) developed the fighting game WaTa Fight. Playtesting
with mixed-visual-ability groups has shown the game stimulated sociality and
the sense of integration.

Jeremy Kaldobsky is an active audio game developer333Aprone’s Accessible
Software and Games. https://www.kaldobsky.com/ssl/audiogames.php (Last visited
on September 16th, 2020), whose most games feature minimalist graphics. One
example is Swamp which is referred to by blind gamers as one of recent games
played with sighted friends and family (Andrade et al., 2019). Hicks et al.
(Hicks et al., 2019) have shown that graphics, even when purely functioning as
an embellishing element conveying redundant information, improve player
engagement. Similarly, past work suggests that appealing graphics in audio
games are an important factor to engage sighted players (Gonçalves et al.,
2020).

Previous work has also explored game design for groups with different motor
abilities (Brederode et al., 2005; Gerling and Buttrick, 2014). In Last Tank
Rolling (Gerling and Buttrick, 2014), one wheelchair-user and one able-bodied
player collaborate in a war scenario. The first player controls a war tank
with the movement of their wheelchair and the second controls a soldier using
full body gestures. Graf et al. (Graf et al., 2019) designed iGym, a
competitive air hockey inspired exergame, with “adjustable game mechanics” to
allow for mixed-motor-ability play. The authors discuss how the adjustment of
parameters, in some cases, ensured fair competition by suppressing the
advantage of able-bodied players and, in others, it was perceived as an
undesirable measure that only reversed the advantage by over facilitating the
challenge of players with motor disabilities.

There is research into Universally Accessible (UA) Gaming (Grammenos et al.,
2009). Namely, there’s the adaptation of traditional games like chess
(Grammenos, 2005) and tic-tac-toe (Ossmann et al., 2008) as well as complex
games that include free world navigation (Trewin et al., 2008a). This work is
incredibly informative for game accessibility by discerning a diverse set of
accessibility design options and integrating them into practice. It proves to
be above all very important for the establishment of accessibility guidelines,
which are now published and disseminated in various forms (Hamilton et al.,
2012; Bors, 2015; Miesenberger et al., 2008; Grammenos, 2008). Grammenos et
al. (Grammenos et al., 2006), following an UA Gaming approach, present the
concept of Parallel Game Universes. In this, customized profiles are used to
adapt the interface and difficulty to the player. This way, players can play
in different ’game universes’, which are bonded, in this case within a
cooperative experience. However, by proposing the same role and task to both,
the solution proposed is to reduce the difficulty of the game for players who
cannot keep up with the challenge. We point out the negative effect of this
specific approach — the portrayal of players with disabilities as less capable
and their contribution as less valuable.

###  2.3. Asymmetry in gaming

Asymmetry can arise at various levels in gameplay (e.g. players have different
character abilities). In some games a complete asymmetry is included within
the design (i.e. players have very different ways of interacting and share
little or no mechanics) (Fullerton, 2008). For example, Cook, Serve,
Delicious! (Vertigo Gaming Inc., 2012) has a co-op mode where one player is
cooking and the other player is managing orders. In Clandestine (Logic
Artists, 2015), players play two interdependent roles — the spy, which
involves a typical third person stealth gameplay and the hacker, responsible
for cracking infrastructure and defeating security systems through a birds-eye
view of the map and a grid display. It’s heavily reliant on patience,
communication and teamwork, since the contribution of the two players is
imperative for the secret infiltration success.

Harris and Hancock (Harris and Hancock, 2019) found, through a study with a
collaborative two-player game, that social presence and connectedness are
higher in asymmetric play than in symmetric play, and even higher when
tightly-coupled collaboration (i.e. higher interdependence) is involved. It
has previously been argued that assuming an explicit asymmetry in gameplay
could be a way to cater for different players and their preferences (Gonçalves
et al., 2020; Credits, 2015). Asymmetry has previously been used in research
for the design of mixed-ability games, although the focus was not the use of
asymmetry — in aforementioned research (Grabski et al., 2016; Gerling and
Buttrick, 2014; Graf et al., 2019). Notably, in Last Tank Rolling (Gerling and
Buttrick, 2014), the movement of the wheelchair is metaphorically and
physically linked with the control of a virtual war tank, which is tougher and
more powerful, but slower than the foot soldier controlled by the second
player. In this example, each role is designed according to the abilities of
each player, turning what is normally portrayed as a limitation (the use of a
wheelchair) as an empowering element and a valuable contribution. Also, the
emergent interdependence of such setting was a catalyst for social play. To
the best of our knowledge, asymmetric roles have not been further explored or
evaluated in mixed-ability contexts.

##  3\. Ability-based Asymmetric Roles in Mixed-Ability Gaming

Wobbrock et al. (Wobbrock et al., 2011) introduced the concept of ability-
based design as a replacing set of questions to model accessible computing.
Ability-based design is grounded on “what can a person do?”, emphasizing that
the focus is on abilities, not on limitations. It places the responsibility
for adaptation in the system, which should be user-adaptable (universally
usable). It’s noted that universal approaches often search for “what can
everyone do?”, while ability-based takes it from a design-for-one perspective,
that asks “what can you do?”. Similarly, our work is influenced by the Social
Model within disability studies, where the disability is not within one’s
body, but in the oppressive social environment (Marks, 1997), as games are
designed for one stereotypical user (Gonçalves et al., 2020) disregarding
mixed-ability play.

More recently, Bennett et al. (Bennett et al., 2018) point out the negative
side of assuming people’s independence as the goal of accessibility, being
that everyone is actually interdependent, relying on others for sustenance,
community, and care. From this perspective, the use of assistive devices can
provide full autonomy to the user, but can also picture users as “vulnerable
or incapable”. The advantages of acknowledging the essential interdependence
existing between all humans are highlighted. Authors argue that an
interdependence frame established in personal relationships may emphasize
contributions from people with disabilities and defy traditional hierarchies
that rank abilities (Bennett et al., 2018).

###  3.1. Concept

From this framing comes the idea of an asymmetric gameplay in which each
player performs ability-based tasks, contributing to a common goal — an
interdependent group of players that rely on each other to succeed. In short,
instead of looking for a single gameplay that can be experienced by players
with different abilities, in this approach we explore the entwining of
different gameplays in an interdependent collaboration as a potentially
effective design choice to achieve an engaging and challenging game to both
players [Table 1].

Table 1. Concept Table. Concept |  Description
---|---
Ability-based |  Challenges are designed based on people abilities (through visual/auditory challenges). The auditory role is vision-independent — the task is not easier for a sighted person. The auditory role has complementary graphics (important for low vision) but they do not offer an advantage. Similarly, the visual role may have complementary music and sound effects but they are not relevant to the challenge.
Complete asymmetry |  Roles intersect in game dynamics (collaboration, communication), but not mechanics — mechanics are radically different.
Collaboration |  The cooperation of two or more people is necessary, as one person would not be able to perform all tasks on their own.
Interdependence |  Players depend on each other to succeed. Avoid the perception that one player is being “assisted” by another.
Agency |  There is decision making on the part of both players. The actions of one influence the other. Avoid the perception that one player is just an “executor” of the game or another player’s orders.

##  4\. Testbed Games

We designed and developed two games as a proof-of-concept. Below we describe
our design process and technical aspects of development.

###  4.1. Design process

We used the three-tiered model of Hunicke et al. (Hunicke et al., 2004) as a
framework to ideate. This model describes how a game is perceived from two
different perspectives — as in designing the game and as in playing the game.
These three layers are Mechanics (i.e. operations and actions afforded),
Dynamics (i.e. emerged behaviors and strategies) and Aesthetics (i.e.
perceived aspects by the player). Our design process starts with the
conception of mechanics mapped to abilities — actions and challenges that
depend, for one role on visual abilities and, for the other on auditory
abilities. We then proceeded to think about how these mechanics could work in
the context of a collaborative dynamic between two players, in which player
actions are interdependent. The collaborative dynamics were discussed and
iterated, leading to changes in the mechanics associated with each role and
the synergies between them.

The concept of both games comes from picturing ways in which no player has
complete information or control over a character, ensuring both game roles are
essential to be successful. In the first game, “Rescue: Under Pressure” (sub),
the player with visual-based interaction is able to move the character (direct
control) and the player with audio-based interaction has a global perception
of the scenario (world awareness). Inspired by how sonar-like abilities were
used before in audio-based world navigation (Westin, 2004; Andrade et al.,
2020), in our first game two players control a submarine, one controlling the
sonar (auditory challenge) and the other drives the submarine (visual
challenge).

In the second game, “Rescue: Mayday” (air), we reversed the mapping of roles
to abilities. One player pilots a rescue aircraft through audio-based
interaction and the second is an air traffic controller, with a strong visual
task. We drew inspiration from how airline pilots typically do not fly based
on visual information and have to rely instead on the instruments and
instructions of air traffic controllers.

Communication is essential between the two players to achieve success. This is
the basis of play and collaboration in both games. We ensured that there is
considerable diversity in what each player can do. As such, various ability-
based mechanics and synergies were designed to fit this collaborative dynamic.
Mechanics imply different skills such as memory, dexterity, which could turn
to be inaccessible in other mixed-ability contexts. We could have built the
visual role as a mix of visual and auditory challenges (since we did not
consider hearing impairments), but we chose to focus the challenges of each
role on one sense. We used the word “Pilot” to name the role of the player who
has direct control over the character and “Engineer” to name the role of the
player who has world awareness. For a detailed characterization of each role,
see Table 2.

###  4.2. Development

We used Unity444Unity. https://unity.com/ (Last visited on September 16th,
2020) to develop the two online multiplayer games. All graphics were designed
from scratch and sound effects were collected from various free sound
libraries and post-edited. All game menus and options are accessible via
keyboard with pre-rendered (and post-edited) speech from open-source text-to-
speech software. Screen readers do not interact with any game elements
(including menus). During development we recruited sighted-sighted (i.e.
researchers with screen reader expertise) and mixed-visual-ability playtester
pairs, whose valuable feedback was critical to ensure usability. We made
available a version for Windows and a version for OSx. A trailer video that
presents both games is available555Games Trailer: https://youtu.be/Sgxxgt-
favA. Games are also available for download666Games Repository:
https://osf.io/2z3tq/?view_only=8ebb305d04c14552be9b9ed57e3e81f2.

Table 2. Roles and mechanics detailed description Role / Tasks |  Rescue: Under Pressure |  Rescue: Mayday
---|---|---
PILOT |  Visual challenge |  Auditory challenge
Moves and acts on the character |  Drives the submarine; Switches between different modes (Collect, Flare, Shoot and Battery Saving). |  Pilots the airplane (auditory compass); Lands and takes off; Switches between airplane and helicopter mode.
Identifies near elements |  Spots ores, enemies, blocked passages and the treasure within the light around the submarine; Flares light up the cave. |  Audio feedback when the airplane is over rescue spots or under storms; Danger sensor beeps when there’s hazards ahead.
Interacts with those elements |  Operates mechanical claw to catch ores; Shoots torpedoes to incapacitate monsters and open blocked passages. |  Opens floodgates to extinguish fires; Maneuvers the helicopter and operates the rope to rescue people.
Supply resources to the Engineer |  Collects ores that are used by the Engineer to charge the battery, upgrades sonar and craft various items. |  Answers SOS calls that are redirected to the Engineer (with coordinates and time limit); Regularly reports airplane position.
ENGINEER |  Auditory challenge |  Visual challenge
Basic information of the world |  Binaural soundscape gives information on the position and proximity of a monster and treasure (passive sonar). |  Map screen with control stations marked; Sees airplane position when the Pilot reports its position.
Actively gathers more information |  Sends pulses that detect ores, monsters and the treasure with information on their position; Upgrades sonar range. |  Marks rescue spots on the map according to coordinates of received SOS calls; Sends pulses to detect storms and other airplanes.
Manages various aspects |  Controls battery level (charging it when necessary); Crafts and load items for the Pilot to use (flares and torpedoes). |  Watches over the water tank level and the state of the vehicle; Regularly consults the time limits for each task.
Provides verbal guidance to the Pilot |  Communicates a direction (e.g. “North”), ensuring the Pilot is able to find ores and the treasure, and to avoid monsters. |  Communicates a direction (e.g. “North”), ensuring the Pilot is able to reach rescue spots, and to avoid storms and other planes.

###  4.3. Games description

Both games imply a synchronous interaction in which players have to be
efficient to achieve the goals within a time limit. Both games include a
tutorial mode and a mission mode and require two players. One player plays as
the Pilot and the other as the Engineer. The tutorial guides each player
through all available mechanics associated with their role as if they were
playing mission mode. The only difference is no time limit to any task, and
the prompts to introduce each mechanic gradually. Players have to cooperate to
fulfill their tasks. In mission mode, there are mechanics that impose time
limits to certain tasks, the objectives, resources and challenges are
quasirandomly generated (e.g. in sub ensuring the treasure is at a certain
depth). Although the games have a very similar collaborative dynamic, the
objectives and the way they manage to achieve them are quite different from
game to game.

In sub, two players collaborate to rescue a lost treasure using a submarine.
Players lose when battery runs out or if the submarine is devoured by a sea
monster. The Pilot drives the submarine and operates various tools [Fig. 1 \-
A]. The Engineer operates the sonar and uses resources to craft items and
upgrades (auditory challenge). They must guide the Pilot, by actively
surveying the submarine surroundings using the sonar in the eight cardinal
points [Fig. 1 \- C].

In air, two players collaborate in air rescue missions with the goal to finish
the day without any casualties. Players lose when rescue missions reach a time
limit or if aircraft collides with a commercial airplane. The Pilot lands,
takes off and pilots the aircraft, operates various tools and regularly
reports the aircraft position (20 seconds cooldown) [Fig. 1 \- B]. The
Engineer controls air traffic, marks the location of rescue operations and
must guide the pilot to them [Fig. 1 \- D]. A description of role tasks and
mechanics is presented in Table 2 and more detailed information about the two
games is also available777Games Detailed Description:
https://osf.io/rktz2/?view_only=720e3f6b788b4e05bb93d6708e7b4e44.

##  5\. Study

We conducted a remote user study with mixed-visual-ability pairs. Our goal was
to understand the potential of the approach in creating inclusive and balanced
gaming experiences for players with different visual abilities. Seeking to
answer the aforementioned research questions, all pairs played both games. Our
research questions focus on understanding how asymmetric ability-based roles
impact players’ perceptions. To understand the effects of asymmetry
irrespective of type of role played, we developed two games to ensure players
could experience both. We also expected gaming preferences (i.e. type of game,
type of role) to impact perceptions. Thus, it allowed us to situate players’
feedback. Participants completed one questionnaire after playing each game
successfully (tutorial + mission). Lastly, participants completed a debriefing
questionnaire where we encouraged them to reflect upon the experience. The
study was approved by the Ethics Committee of our school.

###  5.1. Participants

We recruited 26 participants, 13 pairs, from 4 countries, aged 16-53 (M=32.31;
SD=8.54) [Table 3]. We made an effort to recruit people with different gaming
experiences by publicizing the call in dedicated gaming forums and
institutions’ social networks. We reached expert gamers, casual gamers and
also people who are not used to play [Table 3]. People applied to participate
in pairs (one person had to reach out and sent both contacts). One pair
element was required to be a screen reader user due to visual impairments
(B1-B13) and the other sighted (S1-S13). 8 participants were totally blind
(i.e. no light perception) and 5 participants (B2, B4, B6, B7, B8) were near
totally blind (i.e. visual acuity lower than 20/1000). Participants could not
have other kinds of severe impairments (mobility, hearing, cognitive), since
games were not designed considering other disabilities.

We purposefully recruited pairs of two non-stranger volunteers (family,
friends, etc.) to assess how asymmetry could be leveraged in mixed-ability
scenarios where people were already familiar with each other. We chose to
evaluate with familiar pairs for two reasons: 1) to enable friends and family
to play together (given the lack of opportunities for these experiences to
happen, highlighted by previous work (Gonçalves et al., 2020)), and 2) to
ensure participants had a baseline of previous interactions with each other.
Also, social closeness, competence and autonomy could be affected by other
factors among strangers, and are out of the scope of this work. We compensated
all participants who fulfilled the protocol with a €25 (or local currency
equivalent) voucher, for their time.

Table 3. Demographic information, gaming frequency and participation details of participants (each row represents a pair); Playtime values represent time to complete the tutorial (T) and time playing mission mode (M) and are always rounded down to minutes. ID | GN | Age | Plays | ID | GN | Age | Plays | Relation | Country | sub Playtime | air Playtime
---|---|---|---|---|---|---|---|---|---|---|---
B1 | F | 34 | Daily | S1 | F | 53 | Monthly | Friends | Australia | 27 (T) 18 (M) | 22 (T) 14 (M)
B2 | M | 28 | Monthly | S2 | F | 26 | Occasionally | Family | USA | 18 (T) 11 (M) | 20 (T) 31 (M)
B3 | M | 41 | Daily | S3 | F | 16 | Occasionally | Family | UK | 31 (T) 21 (M) | 17 (T) 31 (M)
B4 | M | 38 | Monthly | S4 | M | 38 | Occasionally | Friends | Portugal | 24 (T) 17 (M) | 15 (T) 18 (M)
B5 | F | 16 | Daily | S5 | M | 18 | Weekly | Family | USA | 15 (T) 38 (M) | 16 (T) 15 (M)
B6 | M | 32 | Occasionally | S6 | F | 27 | Occasionally | Partners | Portugal | 21 (T) 18 (M) | 21 (T) 29 (M)
B7 | F | 40 | Never | S7 | F | 32 | Weekly | Friends | Portugal | 24 (T) 68 (M) | 44 (T) 21 (M)
B8 | M | 38 | Occasionally | S8 | F | 36 | Occasionally | Family | Portugal | 21 (T) 20 (M) | 41 (T) 19 (M)
B9 | M | 33 | Weekly | S9 | M | 31 | Monthly | Friends | Portugal | 27 (T) 53 (M) | 23 (T) 35 (M)
B10 | F | 41 | Never | S10 | F | 38 | Occasionally | Friends | Portugal | 38 (T) 23 (M) | 48 (T) 27 (M)
B11 | M | 25 | Monthly | S11 | M | 26 | Weekly | Friends | Portugal | 23 (T) 11 (M) | 26 (T) 19 (M)
B12 | M | 37 | Never | S12 | F | 37 | Daily | Family | Portugal | 33 (T) 23 (M) | 51 (T) 12 (M)
B13 | F | 35 | Occasionally | S13 | F | 24 | Occasionally | Family | Portugal | 48 (T) 32 (M) | 58 (T) 30 (M)

###  5.2. Procedure

After filling out the participant form, pairs were contacted via email with
instructions and the link to the first game they were required to play. Games
were counterbalanced between pairs. Participants had at least one week with
the first game and were asked to complete the tutorial (about 20 minutes), and
play the mission mode for another 10 minutes. We suggested recording their
game session (screen capture + communication audio), but did not make it
mandatory. After meeting the requirements, each participant received an email
to fill in the questionnaire about the experience (detailed below).
Participants were free to continue playing if they wished to. After at least
one week, and after completing the experience questionnaire, participants were
contacted and given access to the second game (same protocol as described
above). After complying with the terms regarding both games, participants had
to complete one last online questionnaire about their final thoughts on the
approach. All play sessions were carefully analyzed, searching for unexpected
difficulties (e.g., quitting the game in the middle of the tutorial). When it
happened, we contacted the participants and asked if they had any problems
playing, offering our help. Participants were also encouraged to reach out to
us if they had any issue or question.

###  5.3. Online Questionnaires

Participants completed four online questionnaires: demographics and gaming
habits (Q1), game session (Q2 and Q3) and debriefing (Q4). All questionnaires
were built in Microsoft Forms and tested for accessibility.

Q2 and Q3 consisted of the Ubisoft Player Experience Questionnaire (UPEQ)
(Azadvar and Canossa, 2018) and open ended questions. UPEQ comprises subscales
of Autonomy, Competence and Relatedness and its 21 items are measured on a
5-point Likert scale, where higher is better. We adapted three items to
instead of referring to “characters” to refer to either “submarine” or
“aircraft”, according to each game. Additionally, we removed the question
“Other players are friendly towards me” in the relatedness’s subscale, as in
the context of our study players were not playing with strangers. The open
questions asked the participants about their experience and thoughts on the
roles. Q4 consisted mainly of open-ended questions that probed participants’
final thoughts regarding the games and the concept. Questionnaires are
available888Study Online Questionnaires:
https://osf.io/86sye/?view_only=31311e7aff1c47f295b89a5f0dc340e8.

###  5.4. Data analysis

We conducted an exploratory study aiming to uncover possible relationships
between the concepts of interest without pre-established assumptions or
hypotheses. We performed a mixed deductive and inductive thematic analysis
over all open-ended questions of the survey, undertaken in line with Braun and
Clarke’s suggested strategy (Braun and Clarke, 2006). We first familiarized
with the data, by iteratively reading the answers. Even before we collected
the responses from all participants, we started to annotate relevant phrases
and recurring ideas in the text. We created an initial set of codes
deductively informed by our readings and enriched with the concepts that stem
from our research questions (e.g. asymmetry, competence, autonomy). Codes were
discussed among the authors, revised and added, as more responses were
submitted in multiple sessions. In these sessions, using Zoom shared virtual
white board, themes were discussed, codes were aggregated in a shared placed,
relationships were identified and discussed with examples (quotes) spread
throughout the board that illustrated the themes that led the research team
discussions. Three authors were involved in the coding process. The final
codebook and outline of the themes are available999Codebook & Themes:
https://osf.io/ydurt/?view_only=bfd44c100f0e4870ab65ee8546f4e0ff.

We used UPEQ to quantitatively measure participants engagement, and analysed
its subscales of autonomy and competence (“each subscale of UPEQ independently
predicts measures of engagement in game and are a reliable alternative for
direct rating of player experience” (Azadvar and Canossa, 2018)). We performed
mixed within-between analysis of variance to assess the effects of game and
user group on UPEQ scores: all reported analysis meet the assumptions of
normality, sphericity, homogeneity of variances, and equality of covariance
matrices. Two pairs recorded and sent us videos of their sessions, which we
reviewed to situate their feedback and illustrate our results.

We chose to assess engagement due to its relationship with players enjoyment
and fun, autonomy as it is intrinsically related with the design concept of
interdependence, and lastly, competence due to its relationship with
asymmetric roles and the past work findings (Andrade et al., 2019; Gonçalves
et al., 2020; Smith and Nayar, 2018) around simplistic or unfair games created
when striving for accessibility. Nonetheless, the study does not focus on the
quantitative measures collected, rather the qualitative data collected is
supported by them.

Using a mixed-method approach, below, we characterize participants’
experiences and perspectives on ability-based asymmetric game roles. This
characterization is primarily based on the thematic analysis of open ended
questions. It is additionally confronted and reinforced by the quantitative
data resulting from the administration of UPEQ, game session logs, video
recordings, demographics and gaming habits.

##  6\. Findings

In sub, players took an average of 27.4 minutes (SD=1.7) to complete the
tutorial and played mission mode for an average of 28.1 minutes (SD=3.2) (over
multiple attempts). In 31 attempts, pairs were devoured by a monster and in 14
they ran out of battery. One pair succeeded in the mission. In air, players
averaged 31.5 minutes (SD=2.9) to complete the tutorial and played mission
mode for an average of 23.6 minutes (SD=1.5). None of the pairs was able to
successfully complete a mission in air, 43 attempts collided with another
plane, and 25 were due to the time limits of the rescue operations. 6 played
remotely and used audio call to communicate, 6 played co-located and were
close enough to communicate, and one pair (B5 and S5) played co-located via
audio call. Individual information about each participant’s game session is
shown in Table 3, namely time playing sub and air.

###  6.1. Enabling mixed-ability digital play

Only two sighted participants (S2 and S13) had previously played games with
someone with visual impairments (both had played tabletop games with their
study partners). Most visually impaired participants reported previous
experiences but pointed out that most games do not meet the different needs of
groups with mixed visual abilities.

> “There aren’t many games that both blind and sighted players want to play
> and can play together. Most games are not accessible and sighted people
> aren’t interested in playing poorly designed blindy games” – B1

The lack of options for group play among people with different visual
abilities was highlighted, which is in line with previous work (Gonçalves et
al., 2020). The games in the study were portrayed by participants as an
exception to the rule. Participants expressed a sense of gratification for
being able to play digital games with friends (“we shared an adventure without
limitations“– S9) and family.

> “I haven’t been able to find any games that are fun for my brother and I to
> play together. […] I feel like it’s a great concept and it was a lot of fun
> being able to play with my brother.” – B5

Participants believed the approach provided an inclusive experience and
attributed its cause to the asymmetry of feedback and tasks. Referencing
asymmetry as: “[…] fundamental aspect to allow inclusive fun.” (B4); “[…]
focused on the best capabilities of each one, games become rewarding for both
players” (S4). One participant highlighted how mixed-ability gaming with
balanced roles, as an inclusive experience, can be leveraged for bonding
activities.

> “[Mixed-visual-ability gaming] inspires bonding between people, trust, team
> spirit. […] If there are games with roles for people with visual impairments
> this can help this integration and equality between partners. I really liked
> the idea, mainly because the person with visual impairments was not given an
> easier or less important role, but a role as important as that of the other
> player.” – B7

###  6.2. Engagement

Table 4. Quantitative data resulting from the administration of UPEQ. All values are presented in mean (standard deviation) pairs, for sub and air, given all participants (A), just visually impaired participants (VI) and just sighted participants (S).  | sub-A | sub-VI | sub-S | air-A | air-VI | air-S
---|---|---|---|---|---|---
Average score | 3.95 (0.08) | 3.89 (0.40) | 4.02 (0.36) | 3.65 (0.11) | 3.68 (0.60) | 3.63 (0.59)
Competence score | 3.67 (0.46) | 3.65 (0.44) | 3.68 (0.49) | 3.09 (0.98) | 3.22 (1.10) | 2.97 (0.89)
Autonomy score | 3.83 (0.56) | 3.76 (0.59) | 3.89 (0.54) | 3.44 (0.68) | 3.41 (0.60) | 3.47 (0.70)

All participants reported a positive experience with at least one of the
games. Regarding overall engagement with sub, participants reported an average
UPEQ score of 3.95 (SD=.08), (visually impaired M=3.89, SD=.48 and sighted
M=4.02, SD=.36). In air, participants reported an average UPEQ M=3.65
(SD=.11), (visually impaired M=3.68, SD=.60 and sighted M=3.63, SD=.59). We
conducted a mixed within-between analysis of variance to assess the impact of
game and user group on Overall Engagement. There was no significant
interaction between user group and game, Wilk’s Lambda=.965, F(1, 24)=8.69,
p=.36, partial eta squared=.04. There was a substantial main effect for game,
Wilks’s Lambda=.706, F(1, 24)=9.99, p=.004, partial eta squared=.29, with both
groups showing to be more engaged in sub. The main effect comparing user group
was not significant, F(1, 24)=.046, p=.832, partial eta squared=.002.

When we asked participants to choose the game they preferred, 19 participants
answered sub and 5 (one of them sighted) answered air. B10 did not answer the
question and B3 chose neither, as he states: “I can’t really pick as I enjoyed
them equally.”

Overall, the experience with sub was significantly more engaging for both
sighted and visually impaired participants. Particularly, sighted participants
highlighted how being the Pilot on sub was more engaging. S2 commented it was
more intuitive and “more fun and easy to move around”. On the other hand,
participants with visual impairments highlighted how immersive was being the
Pilot of the aircraft:

> “I really liked my role. […] I really like using the different controls to
> work on the airplane, going where I wanted it as well. I felt like I was
> actually doing the mission.” – B5, referring to air

In both games, most participants enjoyed the challenge of managing several
aspects at the same time, when playing as the Engineer. However, some
participants perceived the role as limited, admitting they would like to have
more agency in the action (e.g. in shooting monsters, in rescuing people). The
preferences of the players stood out in their perspectives, suggesting changes
in the controls and tasks of their role, and even giving ideas for other games
with asymmetric roles. Particularly, the narrative setting of each game
influenced the feelings of each player, both positively (“I really like the
sea. [..] I really imagined the underwater scenario” – B7), and negatively.

> “Maybe, airplanes, storms and fires are not something I find particularly
> nice. […] Apart from the setting, it was a nice game to play with a blind
> friend.” – S2, referring to air

B5 mentioned she tried to play text-based games with her brother, but pointed
out that, in comparison with these, the games in the study “were fun because
you were actually moving around and doing something”. Audio-based mechanics
were praised by participants with visual impairments, such as the helicopter
mode (“I want more of that” – B2) and active sonar (“Really interesting
concept using sonar to find different types of materials under water.” – B5).

###  6.3. Competence & Autonomy

Regarding sub, participants reported an average competence of 3.67 (SD=.46)
(visually impaired M=3.65, SD=.44 and sighted M=3.68, SD=.49). In air,
participants reported an average competence M=3.09 (SD=.98), (visually
impaired M=3.22, SD=1.1 and sighted M=2.97, SD=.89).

We conducted a mixed within-between analysis of variance to assess the impact
of game and user group on Competence. There was no significant interaction
between user group and game, Wilk’s Lambda=.979, F(1, 24)=.524, p=.476,
partial eta squared=.02. There was a substantial main effect for game, Wilks’s
Lambda=.719, F(1, 24)=9.36, p=.005, partial eta squared=.28, with both groups
showing to feel more competent in sub. The main effect comparing user group
was not significant, F(1, 24)=.204, p=.656, partial eta squared=.008.

Regarding sub, participants reported an average autonomy score of 3.83
(SD.56), (visually impaired M=3.76, SD=.59 and sighted M=3.89, SD=.54). In
air, participants reported an average autonomy score of 3.44 (SD=.68),
(visually impaired M=3.41, SD=.67 and sighted M=3.47, SD=.72). A mixed within-
between analysis of variance showed no significant interaction between user
group and game on Autonomy (Wilk’s Lambda=.996, F(1, 24)=.105, p=.749, partial
eta squared=.004). There was a substantial main effect for game, Wilks’s
Lambda=.701, F(1, 24)=10.23, p=.004, partial eta squared=.29, with both groups
showing to feel more autonomous in sub. The main effect comparing user group
was again not significant, F(1, 24)=.224, p=.640, partial eta squared=.009.

Participants pointed out how the games were challenging, with the UPEQ item -
”I was good at playing” having the lowest average score M=2.63. This suggests
participants did not feel they had mastered the game in a single play session.
As already mentioned, only one of the pairs (B7 and S7) managed to
successfully complete a mission, in sub. They do not play often [Table 3], but
showed enthusiasm for the game considering the time they played (68 minutes,
over 8 attempts) and answers to the survey. In air, two pairs were able to
accomplish three rescue tasks (they extinguished two fires, rescued a person
and landed to deliver the person), but none managed to reach the end of the
mission.

Participants felt significantly more autonomous and competent playing sub than
air. Some perceived air as too challenging which detracted from the
experience.

> “Not knowing the plane’s position on the map more often induces a very high
> degree of difficulty that prevents the game from being more engaging.” – S4,
> referring to air

In air, the Engineer can only see the aircraft’s position on the map when the
Pilot reports it. We have limited the reporting feature to once every 20
seconds. Its intermittence coupled with the aircraft continuous movement made
navigation time sensitive, thus perceived as more demanding. Some pairs felt
frustrated because they were unable to reach the relevant locations to
complete the objectives.

Participants described how they reflected on the experience and identified
points where they could improve as a team, figuring out how to communicate
efficiently. In a particular case, which we were able to observe in full
through video recording, a pair (B4 and S4) found an unexpected way to achieve
an understanding of roles and collaborative dynamics in air. S4 was not
understanding how the aircraft’s navigation worked and was not sure how to
give directions, so the pair decided to reverse roles. Although they were
unable to complete the tutorial (the role of Engineer is not accessible to
B4), it was enough to reach an understanding and to collaborate in harmony. In
this case, participants were unable to overcome one of the challenges that the
game proposes — reach reconciliation through effective dialogue — and made
this curious decision.

The Pilot’s dependence on the Engineer was highlighted by some. However,
others mention, in sub, the Pilot has more freedom to explore and have a
reference of where ores can be, by following the walls.

> “I found there is a logical dependence on the Engineer. But there is also
> the possibility for the Pilot to find an ore [close by]. There is a sense of
> freedom of action.” – S9, referring to sub

In fact, unlike the Pilot in air, the Pilot in sub has a visual reference of
where important elements may be (an idea of ”path”, formed by the
claustrophobic cave). This led to a sense of autonomy, even though, in both
games, the Pilot can only perceive elements at a minimum distance and has no
way of avoiding dangers without the help of the Engineer. This perception is
explicable given that, although there is equivalent information in air when
close to fire and rescue locations, the feedback is more spaced out.

While the approach was effective in acknowledging and suppressing differences
in abilities, other differences had an impact on the experience. For example,
B2 played first sub and explains how the experience has become unbalanced
because his partner “was not an experienced gamer, so it was difficult for her
to find objects and move around the space”. Likewise, after playing air, B2
commented “there’s no way I can help the Engineer be better. So if they are
struggling and I’m just going in circles, it’s not very useful”. This happened
with other pairs. For example, B1, who plays digital games daily, mentions the
role of Engineer in air implied a task in which there was ”too much to
concentrate on for her [partner]”.

This was expected, as players have to be efficient playing their roles to
succeed as a team. Some participants recognized they would have preferred to
have more autonomy during the game: “I wanted to take charge, but my role is
not one that allows me to take charge.” (B2, referring to air). For some
pairs, it is likely that a loosely coupled interdependence would be more
appropriate. B2 adds that “a collaborative game where you’re two separate
entities, like a wood cutter and a builder, would be better, as then we will
be in control of our own section.”.

###  6.4. Equity & Awareness

The collaboration through game roles with tasks and interactions mapped to
abilities was associated with social inclusion. With UPEQ, we did not find
significant interaction between user group and game in engagement, autonomy or
competence. Although experiences with the games were different for all pairs,
for most, games were successful in creating a space to have fun, irrespective
of abilities.

> “In the end, inclusion and team spirit win, and the barriers between people
> become more blurred.” – B6
> “On the other side there was just another player with whom I was having fun,
> and there was no perception that he was a person with a disability.” – S4

For most participants, control over the collaboration was balanced and tasks
were evenly divided through the two roles. Participants mentioned this in
relation to both games. The collaborative dynamic was described as a shift in
leadership from one role to another depending on what the game status
required.

> “I don’t think there was one person who was more in charge. I needed the
> Pilot to control the submarine, but he needed me to find different objects
> and monsters […]. I like that there wasn’t a bigger role.” – B5, referring
> to sub

Games offered different gameplays to each player, which, in this case, allowed
for a balanced joint experience. Participants’ perceptions illustrate how
equality does not mean equity (“[…] giving players a sense of equal
circumstances regardless of their characteristics.” – B6). Moreover, games
showed potential in raising awareness of different abilities, through a social
and playful experience. Participants highlighted how they could be leveraged
to educate people who may have preconceptions about the impact of a visual
disability.

> “It would be a great way of educating sighted people in to what blind people
> can do in a social non-educational environment.” – B3

###  6.5. Information asymmetry

Participants enjoyed how game mechanisms stimulated communication and
interaction between players. This was highlighted in both games, since in both
the Pilot depends on clear and succinct indications, not being aware of what
surrounds them from a distance. One of the challenges both games featured was
the need to figure out how to communicate effectively given the asymmetry of
information available for each player. S1 comments how the games “allow team
work and [are] a great teacher of proper communication between players.”.
Information asymmetry was recognized as the main catalyst.

> “The Engineer and I played next to each other. I could see his screen but it
> didn’t give me any clues, which increased the verbal interaction between us.
> I know the Engineer was notified of the missions being accomplished because
> he cheered.” – S2, referring to sub

The tight communication was a highlight of the experience for most
participants. However the repetitive nature of their tasks made communication
”boring” for some, who suggested alternative forms of communication — e.g.
“like a high five emoji or something visible/hearable” (S2), moving beacons of
light, as well as new game mechanics.

> “I feel like maybe more aspects of the game should be us trying to
> communicate with each other. Like when I drop the rope, he has to guide it
> or something.” – B5, referring to air

Information asymmetry caused tensions between players, as it required pairs to
solve the problem together and establish a consensus despite neither having
all the required information. In the case of S6 and B6, the asymmetric
experience caused divisive moments.

> “The interaction was not so good because, in the beginning, we were always
> seeing who was to blame for not being able to achieve the goal. Me saying I
> was giving the indications of what I was seeing and he saying he was
> following the indications he was hearing.” – S6, referring to air

During design phase, we made decisions to keep information asymmetric, in
order to stimulate communication. For example, we discussed whether in sub,
the Pilot should have graphical indications of battery level and ammunition.
We decided not to, since it is up to the Engineer to control these aspects and
to communicate them to the Pilot. Some pairs were successful in finding an
efficient way to communicate. As mentioned, one pair was more ingenious and
tried to play the tutorial in opposite roles. Participants also highlighted
the unity and trust that must exist between the two players to be able to work
better as a team.

> “We have to trust our game partner and accept the information he gives us.
> Therefore, trust, constant interaction and good communication are essential
> to fulfill the mission.” – B7, referring to sub

###  6.6. Inherent Inaccessibility of Ability-Based Roles

Participants commented how they got to try both roles (Pilot and Engineer)
accordingly to the game, and found the ability-based roles to be fundamental
for inclusion and equity. However, 3 participants (B1, B2 and B13) mentioned
that by having only one accessible role is not very inclusive because the game
cannot be played by two visually impaired people. The way we designed the
asymmetry fits a very specific scenario: mixed-ability pairs. Some
participants mentioned that designing for mixed-ability gaming is “inherently
discriminatory” (B2). Two participants with visual impairments pointed out
that one of the biggest barriers is not having sighted people to play with. It
was suggested that games should allow people with visual impairments to play
among themselves or even to play alone: “there should be a way in which we can
play alone, so we are not always dependent on the availability of another
sighted person.” (B13)

##  7\. Discussion

The study was seen by most participants as an opportunity to share a playful
moment with a family member or friend, with whom they do not usually play.
Seven participants mentioned this was the first experience in which they
knowingly played with someone with a different level of vision. Most
participants pointed out the lack of games that can be enjoyed by both people
with and without visual impairments. In previous work, the lack of
intersection of gaming habits and communities in this context was highlighted
(Gonçalves et al., 2020), which is also emphasized in our results. We
collected valuable feedback from participants’ perceptions we consider to be
informative for research in gaming and accessibility. Some of these
observations are related to the nature of collaborative games and asymmetric
games, but we focused here on issues particularly relevant for mixed-ability
gaming contexts.

###  7.1. Inclusive fun through asymmetry

Participants found the games to be engaging and inclusive experiences, with
some wishing for more content, customization and variety that would enable
them to keep playing together. When it comes to mixed-ability gaming, we argue
it is not just a question of people being able to play. The ultimate goal,
from a hedonic and social perspective, is to design games that people want to
play together. By including two stereotypes in the games through a designed
asymmetry, the needs of each player were met. We did not seek for universally
accessible gameplay. Rather, we focused design on the individual. It
successfully provided an intersection space in which both players felt
included, challenged and engaged and in which differences in abilities were
not limiting. Moreover, we found for most pairs it successfully provided a
balanced collaborative gameplay in which both players felt as valuable
contributors. Although the experience was not equal for both, it provided
equity.

Our findings suggest that, in a context of mixed-visual-ability, ability-based
roles can create engaging experiences for both players, which answers our
first research question. The concept proved to have potential and it should
inspire other researchers and game designers to explore alternative approaches
to achieve inclusive fun, even if they appear to suffer some shortcomings
towards universal accessibility.

###  7.2. Interdependence with ability-based roles

Participants considered the collaboration in both games balanced, in the sense
that none of the players was leading or as if the leadership was constantly
shifting between the roles as the situation required. Both roles, in both
games, were highly interdependent, to the point that communication was
constantly required, which was, for the majority, a highlight of the
experience. The asymmetric nature of the information coupled with the
interdependence of the roles required participants to: 1) figure out a way to
communicate effectively; and 2) trust each other’s judgment and information.
This led to roles where both players felt valuable, necessary and where the
underlying design approach of each role representing an ability did not have
any weight to the overall experience, other than guaranteeing an inclusive
game. These findings inform how interdependent ability-based roles can impact
players’ perceived autonomy and competence, which answers our second research
question.

There were only brief tasks that players could engage on their own (e.g.
collect a found ore, build a torpedo). The tight dependence on each other led
some players (particularly when gaming expertise were diverse in the pair) to
report a lack of autonomy and wish for overlapping mechanisms, feedback or a
different division of tasks. Harris and Hancock (Harris and Hancock, 2019)
have faced this issue when analyzing the impact of different degrees of
interdependence on players’ perceptions. Their results showed that players
felt more connected, engaged and interested when interdependence was tighter.
However, similar to what we found, they also showed that less skilled pairs
preferred looser interdependence. Harris and Hancock present the concept of
rhythm of interdependence, in which the level of dependence between players
varies in intensity and dynamics. We argue that in mixed-ability contexts
using asymmetric ability-based roles, there is an opportunity to explore how
to guarantee a challenging experience for all players without sacrificing the
interdependence and asymmetry that appears to be at the center of both players
feeling necessary, competent and trusted. We believe that, for example, by
providing difficulty customization within each role it is possible to
accommodate players of different expertise levels and maintain high
interdependence.

###  7.3. Different-ability awareness

The educational value of games was recognized in raising awareness of the
capabilities and gaming habits of people with different abilities.
Participants mentioned the experience would be a good way to show how people
with visual impairments are playing digital games. Although the games were
strictly designed to be for mixed-ability contexts, participants highlighted
how even two sighted players with no accessibility awareness could play the
game together and be educated of how blind gamers play.

In multiplayer games, players typically have an equivalent general perception
of the world and the agents in that world (e.g. in a shooter, one player can
see others shooting). In games with complete asymmetry, like ours, players
have very different information and this perception is divergent. Participants
frequently reported the unawareness of the opposite role (i.e. how it was
mechanically and interactively), which in some cases aroused curiosity. This
is due to the nature of asymmetric gameplay and the fact that participants
could not play in reversed roles (one role is inaccessible). Also, to
stimulate communication we made decisions in order to maintain asymmetrical
information as much as possible. From players’ perspectives, we realized the
actions and contributions of each person were for the most part implicit, and
had to be communicated verbally. This overall unawareness by design, was
associated with “blurring” the abilities of each player. In particular,
sighted participants mentioned how they wouldn’t be able to tell they were
playing with a visually impaired player. This provides an opportunity to
explore asymmetric games, as a multiplayer entertainment for visually impaired
players, where their disabilities do not need to be conveyed or accommodated.

For one pair, asymmetry information gave rise to tension due to the difficulty
in finding consensus. However, the same asymmetry inspired the feeling of
unity and trust. We find a potential to break stigmas and raise awareness
about different abilities. As already mentioned, the individuals who struggled
and had to adapt were the ones with less gaming expertise which is expected
giving the games were designed to be challenging. We see reflected the
potential recognized by Bennett et al. (Bennett et al., 2018) of acknowledging
the interdependence between people — valuing each person’s contributions and
destabilizing traditional hierarchies that rank abilities.

###  7.4. Tensions of Ability-Based Game Design

To minimize the tensions that could arise from having a single role
accessible, and the possible connotations with it, we developed two games
where a different role was accessible in each. In addition, the two different
contexts of play enabled us to explore asymmetric ability-based roles where
there is a certain equivalence between the same role in different games [Table
2]).

We acknowledge that having roles inaccessible by design can be controversial,
particularly when we consider how difficult it is to get someone sighted to
play with, due to the isolated gaming communities. During our recruitment we
were contacted by 6 more visually impaired people who wished to participate
but did not have any sighted partners they could play with. We argue that the
isolated communities and lack of mixed-ability play is a symptom of the lack
of balanced and engaging opportunities to play which we address with our
approach, by design. Previous work cautioned about the negative effects found
in other contexts where there is a separation of technologies (Hazard, 2008).
In this study, we found that assuming an explicit asymmetry in gameplay
provided an inclusive, engaging and challenging experience for mixed-visual-
ability pairs which is not readily available elsewhere.

Accessibility should not be an a posteriori effort to adapt something to the
needs of people with disabilities. This seems to be recurrent in gaming
accessibility. We argue it should be about finding ways to include these
different needs from the beginning of the concept and design process. It is
urgent to think of the population as the complex and diverse compound that it
is and to find ways to close the gaps that divide different communities,
either because of their abilities, their age, or culture. The more work there
is, the more faded the perception that games (and more) have to be done for a
single stereotypical player without disabilities and the closer we will be to
a world where differences exist and they are proudly embraced by design.

###  7.5. Limitations

We conducted a fully remote study with asynchronous communication with
participants. As such, we could not control aspects such as the Internet
connection of participants, devices they used to play, etc. Although our game
prototypes were able to detect disconnections, they were unable to reconnect
if the connection was lost for an extended period of time (above 10 seconds).
One group, unfortunately, was unable to participate due to frequent connection
issues.

Past work has highlighted the lack of opportunities for mixed-ability play,
and how audio games are not appealing to sighted players. Thus, although we
found our games to be overall engaging, participants have none to limited past
experiences playing together.

It is important to note that these games are prototypes, which are probably
not at the level of what participants are used to playing. Although most
participants had an engaging experience, it was also associated with tedious
moments as the tasks and the way players solved them started to get
repetitive.

##  8\. Conclusion

Recognizing that mixed-ability digital play remains rare, we sought to explore
a different approach to game design that caters for different abilities. We
created prototypes of games in which there’s a complete asymmetry in the
gameplay design based on stereotypical abilities (i.e. visual and auditory).
Although we focused on mixed-visual-ability pairs, we believe the approach is
promising to any mixed-ability context, where roles are designed based on a
chosen set of abilities. We showed the approach was able to provide an
inclusive experience unlike the games participants usually play. Our work
shows the potential for novel approaches where equity does not necessarily
come from equality.

###### Acknowledgements.

We kindly thank all of our participants. This work was supported by FCT
through LASIGE Research Unit funding, ref. UIDB/00408/2020 and ref.
UIDP/00408/2020, Portugal-UK Bilateral Research Fund (PARSUK BRF) through
project “INPLAY: Designing games for inclusive play with the visually impaired
and sighted”, and the UKRI Centre for the Analysis of Motion, Entertainment
Research and Applications (CAMERA 2.0; EP/T022523/1).

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