Aliens versus Humans: Do avatars make a difference in how we play the game? Chris Christou*† Despina Michael* *GETLab, Cyprus University of Technology, Limassol, Cyprus. †University of Nicosia, Nicosia, Cyprus. christou.ch@unic.ac.cy, despina.michael@cut.ac.cy Abstract— an immersive first-person 3D computer game was designed and developed to investigate if the visual characteristics of a player’s avatar influences their behavior. Two types of gender-matched biped avatar were used: Normal looking Humanoids and tougher looking Aliens. In the game, players had to block incoming projectiles fired from two canons with their hands. The number of times the players were hit as well as a measure of how hard they hit the projectiles was recorded. Results show differences in these measures dependent on the type of avatar used, in line with previous findings whereby people appear to be influenced by the perceived characteristics of their digital representation. Keywords—virtual reality; avatar; first-person computer game; immersive VR; body ownership; Proteus Effect; self-perception I. INTRODUCTION An avatar is the graphical representation of a participant in a digital simulation. With the development of online virtual communities such as Second Life and multiplayer games such as World of Warcraft in which the participants choose, and even customize, their avatar these graphical entities have become an expression of digital identity. Psychologists have therefore started to probe the effects avatars have on communication and social interaction e.g. [13, 8, 9]. There appear to be two themes: the influence an avatar has on other participants in a virtual setting and the influence the avatar itself has on its owner. Findings from both fields have important implications for the design of digital games. The computer games industry invests substantial amounts of effort and money in designing the central characters of their games and therefore the avatars the players will adopt. Any findings from these two areas of research may therefore have substantial impact on this important aspect of the interactive entertainment industry as well as the academic field of psychology. A. Avatars in Games One of the fundamental decisions for a 3D game developer is the choice of perspective for the player and therefore the form taken by the player’s avatar. There are two choices: First- person perspectives and third-person perspectives. The former entails the player and avatar having the same vantage point. That is, the player’s perception of the world coincides with that of their avatar because the graphical perspective coincides with the avatar’s eyes. In the latter, the player sees their avatar from a vantage point outside of their virtual bodies and as such can see the character they are controlling from a distance. One possible benefit of the first-person perspective is that the player can identify more with their character and become more immersed in the virtual scene in which the action takes place. First-person shooters, for example, became a genre of video games in their own right and defined the era of the video games console with notable examples such as Doom, Half-Life and Halo. Like most games, first-person shooters involve an avatar that is controlled by using either a keyboard or joystick. The player can move through the 3D scene, point and shoot a gun, and view a head up display of their health and ammunition. In traditional computer games the player could not see much of their avatar which was limited to arms, hands or just their weapon of choice. As games evolved the avatar became more important. Indeed, in Massively Multiplayer Online Games (MMOG), a genre of video game in which players play against each other, players choose their avatar and customize them. This endows players with an online personality and the potential to make a statement to their co-players. Furthermore, with the recent release of the Oculus Rift head mounted display (HMD) we expect that avatar characteristics will become even more important. This is because the Rift provides fully immersive viewing. The view of the scene displayed in the HMD is updated according to head movements and therefore players may rotate their heads to see their avatar’s arms, legs and even parts of their torso. In this case the sense of identity between the player and their avatar is established even more. The question we may ask is does the appearance of the avatar make any difference to the players’ psychology and therefore how they play the game? In the next sections we briefly review two lines of research that suggest that it does. B. Body Ownership The phenomenon of body transfer or body ownership derives from the ‘Rubber Hand Illusion’ [10] in which subjects see a rubber hand located in front of them while their corresponding (real) hand is hidden from view. If participants see their rubber hand being stroked while simultaneously their real hand is stroked in the same way they have the illusion that the rubber hand is their own: so much so that they display anxiety and reflex behaviour when the rubber hand is