Play Commander Keen 3: Keen Must Die! Online

Commander Keen 3: Keen Must Die! is a side-view platform game released in 1990 for MS-DOS. Developed by id Software and published by Apogee Software, it is the third title in the Commander Keen series. The game follows the young protagonist as he travels to the Vorticon home planet to confront the Grand Intellect, the entity that commands the Vorticon forces.

Players control Commander Keen across a series of levels accessed from a top-down map of the planet. The primary objective on each level is to navigate to an exit point, which returns the player to the map screen. Progression involves moving through environments filled with enemy creatures, such as various Vorticons, and environmental hazards like pits. If Keen is hit by an enemy or falls into a hazard, the player loses a life and is returned to the map.

Gameplay systems include using a raygun to defeat most enemies and a pogo stick for enhanced jumping ability to reach higher areas. Throughout the levels, players can collect items such as keycards to open locked doors and bonus items that contribute to a score tally. Accumulating enough score grants an extra life. Another collectible, the Ankh, provides a temporary state of invulnerability to hazards and enemies.