Play Commander Keen 2: The Earth Explodes Online

Commander Keen 2: The Earth Explodes is a side scrolling platform game released for MS DOS in 1990. It is the second title in the original Commander Keen trilogy, developed by id Software and published by Apogee Software. The game presents a science fiction scenario where the player must prevent an alien attack on Earth.

The player controls the young protagonist, Billy Blaze, also known as Commander Keen. The primary objective is to navigate a series of levels aboard a Vorticon mothership to locate and destroy several X 14 Tantalus Ray weapons before they can be used. Progression is structured around a top down map screen that serves as a hub, allowing the player to select individual platforming stages to enter. Each stage requires finding an exit to return to the map, with specific stages containing the critical ray weapons that must be disabled first.

Gameplay involves running and jumping through environments filled with hostile creatures and environmental hazards. The character can use a raygun to defeat certain enemies and employs a pogo stick for extended vertical jumps. Players can also collect keycards to access locked areas and gather various bonus items that contribute to a score tally, with extra lives awarded for reaching certain score thresholds. Contact with enemies or hazards results in the loss of a life and returns the player to the overhead map screen.