Tab ↹ + M - Display how much memory is in use.Tab ↹ + I - Free items (gives you 100,000 points, extra lives, and lots of ammo plus restores health).Tab ↹ + F - Gives you the coordinates you are currently in.
Once activated, you can press key combos: Start the game with the parameter of -debugmode, then during gameplay press Left ⇧ Shift + Alt + ← Backspace to activate it. None of the boss-type enemies actually use the DeathCam ending in Spear of Destiny. The DeathCam logo, a leftover from Wolfenstein 3D.
