I found the following codes somewhere on the net, but I didn't check them

EPISODES 1,2,3:
   Cheats:
     While in play, hit the following...

     C + T + space ----- gives you: pogo (if You haven't it yet), 99 ammo, and all keycards
     G + O + D --------- You are in God mode (works as jump cheat on pogo)
     shift + tab ------- level bypass (while in the map)


EPISODES 4,5,6,7:
   Cheats:
     While in play hit F10 and one of the following:

     B+A+T ------ Get 99 shots, all keys, and an extra Keen 
     E+N+D ------ Stop game and save everyone (beat the whole darn game)
     F9 --------- Boss Mode 
     B -----       Change color of border 
     C -----       Displays current # of objects (active and not active) 
     D ----- Record a demo 
     E ----- End level 
     G ----- God Mode 
     I ----- All items 
     J ----- Jump Cheat 
     M ----- Memory usage 
     N ----- No clipping mode (useful only with the map screen) 
     P ----- Pause game 
     S ----- Slow motion 
     T ----- Sprite test 
     V ----- Adds extra VBL's (VBL's??) 
     W ----- Warp to any level 
     Y ----- Shows all secret holes/steps 


NOTES FOR EPISODES 4,5,6,7:
  1. If above combinations don't work try with: A, 2, ENTER  and then F10 with the rest
  2. Maybe You don't need to hit F10 before the following:
                                 -  B+A+T
                                 -  E+N+D
                                 -  F9
  3. In EPISODE 3, I'm not sure that the following:
                                 -  B+A+T
                                 -  E+N+D
                                 -  F9      ,
     exist.


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