Osomatsu-kun Hachamecha Gekijou (おそ松くん はちゃめちゃ劇場) is a 1988 action game by Sega for the Sega Mega Drive tying into the Osomatsu-kun media franchise in Japan, which at the time saw a revival in the form of an anime series stared the same year by Studio Pierrot. It is one of the few Mega Drive games to never receive full support for TMSS, meaning it will only work on most Model 1 Mega Drives.
B shoots balls from a slingshot that only go a short way before disappearing. C jumps; Up+C jumps higher. Up enters doors. Down crouches. Start appears to bring up some sort of weapons menu but the means to navigate it is unknown.