The development of Artificial Intelligence (AI) enables humans to co-create
content with machines. The unexpectedness of AI-generated content can bring
inspiration and entertainment to users. However, the co-creation interactions
are always designed for content creators and have poor accessibility. To
explore gamification of mixed-initiative co-creation and make human-AI
interactions accessible and fun for players, I prototyped Snake Story, a
mixed-initiative game where players can select AI-generated texts to write a
story of a snake by playing a "Snake" like game. A controlled experiment was
conducted to investigate the dynamics of player-AI interactions with and
without the game component in the designed interface. As a result of a study
with 11 players (n=11), I found that players utilized different strategies when
playing with the two versions, game mechanics significantly affected the output
stories, players' creative process, as well as role perceptions, and players
with different backgrounds showed different preferences for the two versions.
Based on these results, I further discussed considerations for mixed-initiative
game design. This work aims to inspire the design of engaging co-creation
experiences