Commander Keen is a side-scrolling platform video game: the majority of the game features the player-controlled Commander Keen viewed from the side while moving on a two-dimensional plane. The player can move left and right and can jump, and can use a pogo stick to bounce continuously and jump higher than they can normally with the correct timing. The levels are composed of platforms on which Keen can stand, viewed from the side as in the original Commander Keen in Invasion of the Vorticons trilogy, and some platforms allow Keen to jump up through them from below. The game also includes moving platforms and teleporters that Keen can respectively jump on and interact with. In between levels, the player travels on a two-dimensional map, viewed from above; from the map, the player can enter levels by approaching the entrance. Once entered, the only way to exit a level is to reach the end, or by resetting the game. When a level is completed, the player is given a password that records their progress, lives, and points; this password is entered when starting the game in order to resume where the player left off. The game is divided into three worlds, connected by a central hub area where the game begins and where Keen starts whenever a password is entered.
