As first-person shooter (FPS) games become highly competitive game genres, various supports are needed to improve the gaming environment. In the past, players have focused on gaming mouses and displays, which are expensive and challenging to select from. To understand the influence of the player’s tension on FPS game control, we developed a system that can automatically adjust the speed of the mouse according to the player’s real-time heartbeat during the game. In this study, we developed and evaluated a system to improve the FPS game environment based on the heart rate.