When you are at the versus screen before a match starts, the first player enters the first three digits and the second player enter the last three digits.

911-911 Armless Kombat
020-020 Blocking Disabled
090-090 Breakers Disabled
022-022 Dark Kombat
391-193 Double Dash
222-555 Dream Kombat
051-150 Enhance Moves Disabled
227-227 Explosive Kombat
001-001 Foreground Objects Disabled
808-808 Headless Kombat
012-012 Health Recovery
091-091 Hyper Fighting
770-770 Invisible Kombat
831-831 Jumping Disabled
931-931 Kombos Disabled
900-900 No Blood
404-404 Power Bars Disabled
707-707 Psycho Kombat
303-303 Quick Uppercut Recovery
234-234 Rainbow Kombat
044-440 Sans Power
300-300 Silent Kombat
731-731 Specials Disabled
123-123 Super Recovery
100-100 Throwing Disabled
010-010 Throwing Encouraged
111-111 Tournament Mode
466-466 Unlimited Super Meter
424-424 Vampire Kombat
242-242 XRays Disabled
666-666 Zombie Kombat