Abstract

Visual embellishments (VEs) are design elements that support information already
conveyed by other means. In games, a similar concept is known as juiciness, and
refers to the provision of superfluous feedback in situations where a single player
action triggers multiple non-functional reactions. Elements that could be considered
VEs are commonly found in games as a way of improving the feedback loop of the
game. While feedback elements have been previously investigated, juiciness remains
relatively undefined and is underexplored.
In this thesis, this issue is addressed through the creation of an empirically grounded
definition of juiciness, and an empirical exploration of how the concept affects player
experience. First, this project presents a literature review of existing research in
this area, exploring the undying motivation through interaction design principles.
It then presents a framework for juicy design built from a survey of game designers
perspectives. This framework is then applied through several user studies that explore the impact of juiciness on player experience. The first user study explores the
effects of VEs with 40 participants comparing the effects of visual embellishments in
two research games created, the Frogger-clone Cuber, and the FPS game Dungeon
Descent. The second study explores the effects of juiciness through the commercially
available game Quake 3 Arena with 32 participants. Building from this, two further
user studies are presented, exploring the effects of VEs in-the-wild through the deployment of the game Cuber, and through a within-subjects study of juiciness and
gamification with 36 participants using an existing research simulation from the life
sciences as research tool.
This thesis defines juiciness as coherent design of game mechanics and visuals, while
providing confirmatory, explicit and ambient feedback. The results of the empirical
work carried out within this thesis show that the effects of juiciness are nuanced, and
can vary depending on both the implementation and context of the juiciness. This
work reveals that juiciness has the potential to target intrinsic motivation factors
and increase the visual appeal of a game. Lastly the overall findings of the thesis
are summarised, followed by a discussion of the wider implications of juiciness, and
its relevance for game development.