Start the game with the "-goobers" command line parameter. Then while playing a game, press [Left Shift] + [Alt] + [Backspace] to enable debug mode. Then, enter one of the following codes to activate the corresponding cheat function:
| Result || Cheat Code |
|Change border color||[Tab] + B|
|Display number of items, doors, and actors||[Tab] + C|
|Skip two levels||[Tab] + E|
|Displays coordinates||[Tab] + F|
|Toggle God mode||[Tab] + G|
|Lose health||[Tab] + H|
|Free items||[Tab] + I|
|Display memory usage||[Tab] + M|
|Pause without message||[Tab] + P|
|Exit game||[Tab] + Q|
|Toggle slow motion||[Tab] + S|
|View graphics and play sounds||[Tab] + T|
|Add extra VBLs||[Tab] + V|
|Level select||[Tab] + W |
|Extra stuff||[Tab] + X|
|Commander Keen Cheat Message|
While playing a game, press A + B + T.
Start the game with the "-baby", "-easy", "-normal", or "-hard" command line parameters.
|Full Health, Ammunition, Keys, And Chain Gun|
While playing a game, press L + I + M.
Note: Your score will reset to zero after this cheat is enabled.
|Infinite Ammunition, Invincibility, All Keys|
While playing a game, press M + L + S.
Start the game with the "Level select" and "Difficulty select" command line parameters.
Start the game with the "-tedlevel [level number]" command line parameter. The level number is a two digit number with the tens digit representing the episode minus one and the ones digit representing the level number minus one.
At the memory screen that appears while the game loads, hold M. Then three music menu options will appear after the game finishes loading.