Commander Keen: Goodbye, Galaxy Cheats for PC

Cheat Mode
To enable cheat mode, start a game and press A + 2 + ENTER. To use it, press F10 followed by one of the following keys:

G - God mode W - Jump level J - High jump N - No clipping I - Free items T - Sprite test D - Record a demo V - Add a VLB M - Get memory usage info E - Restart game S - Put game in slow-mo Y - Makes the game look weird C - Mega-stats

Power-Ups
To receive the pogo stick, key cards, and gun charges easily, press C + T + Space
while playing.

Skip City
To bypass any city on the map screen, press Shift + Tab
and walk through it.