Big Challenge! Gun Fighter is the third in Jaleco's Big Challenge! series of Famicom Disk System games. The player is a cowboy who must make their way across a Wild West town while shooting or avoiding the various enemies, which include rooftop gunmen, boxers and other ne'er-do-wells. The player can find additional ammo and health refills after defeating enemies, as well as money which can be spent at the start of each level on various items.