Commander Keen 4 - 6
Press A + 2 + ENTER key combination to get into Debug mode and use these key combinations:
F10 + J - Jump mode
F10 + G - Godmode
F10 + W - Warp
F10 + E - Complete a level
F10 + N - No clipping
F10 + I - Get items
F10 + B - Change frame colour
F10 + C - Show current amount of objects
F10 + D - Record a demo
F10 + M - Show Memory usage
F10 + S - Slow motion
F10 + T - sprite test
F10 + Y - Reveals Hidden Areas
F10 + V - extra frames
F10 + F9 - boss mode
E + N + D - Complete the entire game