Monte Carlo Tree Search for Collaboration Control of Ghosts in Ms. Pac-Man

In this paper, we present an application of Monte Carlo tree search (MCTS) to control ghosts in the game called Ms. Pac-Man. Our proposed ghost team consists of a ghost controlled by rules and three ghosts controlled individually by different MCTS. Given a limited time response, in order to increase the reliability of MCTS results, we introduce a mechanism for predicting Ms. Pac-Man's future movements and use this mechanism for simulating Ms. Pac-Man during Monte Carlo simulations. Our ghost team won the first Ms. Pac-Man Versus Ghost Team Competition at the 2011 IEEE Congress on Evolutionary Computation (CEC). Its performances for a variety of design choices are also shown and discussed.