Pro Action Replay Codes:
Instantly Beat Each Level - 00D72C:00
1 Hit Until Scratchy Is Dead - 00D72C:01
Infinite Health - 00D6E9:64 -Rune
Invulnerability - 00D6E8:FF

Game Genie Codes:
Invulnerability - 005-52C-191
Start with 4 lives and 4 continues - 002-76F-B30 -Galoob
Start with 1 life - 012-72F-F7A -Galoob
Start with 7 lives - 072-72F-F7A -Galoob
Start with 9 lives - 092-72F-F7A -Galoob
Start with 15 lives - 0F2-72F-F7A -Galoob
Start with very little energy on your first life - 3EE-3D5-B31 + 01E-3E5-F7E -Galoob
Infinite energy - 3AA-CAB-2A2 -Galoob
Almost Invincible - 3E9-14E-4CA + 3E5-54C-4CA -Galoob
Infinite lives - 3A2-E2B-2A2 -Galoob