The following codes must be entered at the password screen. You should use the following key for each character:
L: Leonardo
M: Michelangelo
D: Donatello
R: Raphael
S: Shredder
Now enter the following combos:
S D S D R L D: Abyss
M R M D R M D: Challenge Code Endurance
D S R D M R M: Health
L R S R D R D: Fatal Blow
R S R L R S M: Unlimited Shurikens
R L M R D S L: Lose Shuriken
L S D R R D R: Mighty turtle
D S L R D R M: New Nexus outfit for Donatello
L M R M D R D: New Nexus outfit for Leonardo
M L M R D R M: New Nexus outfit for Michelangelo
R M S R M D R: New Nexus outfit for Raphael
S L S D R D L: Nightmare
M R L M R M R: Pizza Paradise
S R M L D D R: Playmates added to Bonus Materials
D R S L L S R: Poison
D R M S R L R: Self Recovery
M L D S R D M: Squeaking
L D R M R L M: Super Defense Power (Defense x2)
S D L S R L L: Super Offense Power (Attack x2)
R D S R M R L: Super-Tough
S S S M R D D: Toddling