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