In developing games, realism is considered as an important factor to increase immersion. To do this, the paper developed 'Jungle Master' game applying the conventional energy model to movement of monsters in RPG. The main scenario of the game is that animals attack each other in order to survive the competition in jungle. While chasing monster : fleeing monster is in the conventional energy model, it is extended as in order to increase fun. As the results, this paper showed that the energy model can be effectively applied to the real game and monsters can be implemented so that they can move in natural.※ 본 연구는 한성대학교 교내연구비 지원과제임.