A mixed-initiative tool for designing level progressions in games

Creating game content requires balancing design considerations at multiple scales: each level requires effort and iteration to produce, and broad-scale constraints such as the order in which game concepts are introduced must be respected. Game designers currently create informal plans for how the game's levels will fit together, but they rarely keep these plans up-to-date when levels change during iteration and testing. This leads to violations of constraints and makes changing the high-level plans expensive. To address these problems, we explore the creation of mixed-initiative game progression authoring tools which explicitly model broad-scale design considerations. These tools let the designer specify constraints on progressions, and keep the plan synchronized when levels are edited. This enables the designer to move between broad and narrow-scale editing and allows for automatic detection of problems caused by edits to levels. We further leverage advances in procedural content generation to help the designer rapidly explore and test game progressions. We present a prototype implementation of such a tool for our actively-developed educational game, Refraction. We also describe how this system could be extended for use in other games and domains, specifically for the domains of math problem sets and interactive programming tutorials.