Commander Keen 4

Commander Keen 4 was released in 1991, developed by id Software and published by Apogee Software, and for plenty of PC players it’s the first game that comes to mind when they hear the name Commander Keen. You move Keen around a map of the world, choose which level to take on next and then head in to jump, explore and shoot your way through. His pogo stick is a big part of the fun, letting you bounce your way to spots you’d never reach with a normal jump.

The controls are easy to get the hang of. Use the arrow keys to move, Ctrl to jump, Alt to use the pogo stick or enter a level from the map, and press Ctrl and Alt together to fire. Stuck somewhere? Hold C, T and Space at the same time to get the pogo stick, all the keycards and full ammo.

This is the shareware version, so you can play Commander Keen 4 online for free right in your browser, or download it and play offline. Log in and your savegame is stored in the cloud, so you can pick up where you left off on any computer.