In this thesis, I describe a Monte Carlo Tree Search (MCTS) powered tool
that I created to help assess the impact of various design choices for in-development
games built on the Unity platform. MCTS shows promise for playing many games,
but the games must be engineered to oer a compatible interface. To circumvent this
obstacle, I developed a support library for augmenting Unity games, as well as exper-
iment templates in Jupyter Notebook for running machine playtesting experiments. I
also propose ways for designers to use this tool to ask and answer designs questions. To
illustrate this, I successfully integrated the library with It's Alive!, a game I am cur-
rently developing, as well as 2D Roguelike, an open source tutorial game available from
the Unity asset store.3 The integration took fewer than 100 lines of code (see Appendix
B). I demonstrate the tools capability to answer both game design and player modeling
questions, as well as provide the results of the system validation experiments.