In the book, the author proposed the approach of CI (Computational Intelligence) to generate both challengeable and satisfactory game opponent, under the proposed framework of “Player Modeling and Opponent Adaptation”. At the present research, CI refers to MCTS (Monte Carlo Tree Search) and UCT (Upper Confidence Bound for Trees); two prey/predator genre games of Dead-End and Pac-Man are used as test-beds to validate the proposed theory. Contributions of this book includes: “Player Modeling and Opponent Adaptation” as a framework of game AI; strategy-based player modeling; opponent’s challengeable adaptation; and opponent’s satisfactory adaptation.