Commander Keen Trilogy 1 (1-3) cheats and cheat codes for PC

Cheat mode:
While playing the game, press [ALT] + 2 + ENTER to activate cheat mode.

Code - Effect:

Press F10 + Y - Display secretsteps
Press F10 + W - Select any stage
Press F10 + V - Add 1-8 VLB
Press F10 + T - Sprite test
Press F10 + S - Slow motion
Press F10 + N - No clip mode
Press F10 + M - Show Memory usage
Press F10 + J - High jump
Press F10 + I - Infinite objects
Press F10 + G - Invincibile mode
Press F10 + E - Complete the level
Press F10 + D - Record demo
Press F10 + C - Change Actives/Non-Actives objects amount in the level
Press F10 + B - Change margin color 1-15


Alternate cheat mode:

Hold down the keys at the same time.
Keys - Effect:
Hold F1 - Help
Hold F8 - Something strange happens.
Hold SHIFT + TAB -  To walk through a city.
Hold C + T + SPACE - Extra keycards.

God mode:
Hold G + O + D to enable God Mode. In this mode you can walk through enemies.
Use pogostick and hold down CTRL key to utilize jump mode. You need to enter 
this code each time when you enter a city.

Command line cheat:
Start the game with the following command line parameter: NOWAIT
F10-key combos are available like in #3-6.