The game uses a side-view perspective. Keen explores multi-screen stages, defeats or avoids enemies, collects treasures, finds keycards, and reaches the exit. A world map connects the individual levels and allows the player to choose an available route.

Keen can run, jump, climb poles, swim in some areas, fire his raygun, and use a pogo stick. Stages contain hazards, locked passages, bonus areas, and hidden sections. Losing all lives ends the current game, while points and extra-life items support continued exploration.

Study enemy movement before committing to a jump, and use the pogo stick for high ledges and safer landings. Explore side passages for keycards, ammunition, treasure, and extra lives.

Save difficult rooms for careful attempts: raygun shots are limited, and some enemies are safer to bypass. On the world map, choose routes that provide useful resources before entering more demanding stages.