Better attack for Leo - L M L S D
Better attack for Raphael - R D S R L
Better attack for Mikey - M S R M M
To unlock Challenge Mode, defeat Story Mode with all four turtles.
In the Subway Train on Level 2-Nano, you can use this technique to get huge combos. Simply push an enemy into one of the corners between the seats of the train and the wall, and then uppercut him (with R2). Now use regular attacks (with X) to keep him in the air. Time your attacks, and you can keep him in the air for as big of a combo as you want.
Complete a level to unlock it in Stage Select.
In 2-player mode, press X and SQUARE at the same time to get into a stance. Then have your teammate come next to you, face you, and then press X and SQUARE at the same time. You will perform a special team attack where you are thrown into enemies, hurting them.
Fulfill the following criteria to unlock the corresponding characters for Vs.
Casey Jones: Beat Stage 1 with Raphael
Evil Turtlebot: Beat Stage 3 with any turtle
Hun: Beat Stage 6 with Michaelangelo
Splinter: Beat Dojo Stage 3 with Leonardo
Shredder: Beat Shredder with any turtle
Oroku Saki: Beat Saki with any turtle
Yoshi Hamato: Beat Challenge Mode with any turtle
Alternate Costume (Raphael): DMDML
Alternate Costume (Leonardo): LDMSR
Alternate Costume (Michaelangelo): RRLMD
Alternate Costume (Donatello): DDSMS
Attack Power Up (Raphael): RDSRL
Attack Power Up (Leonardo): LMLSD
Attack Power Up (Donatello): DRLDS
Defense Doubles (Leonardo): MRLLM
Defense Doubles (Donatello): SSSMR
Defense Doubles (Michaelangelo): MRRML
Defense Doubles (Raphael): LRMDS
Defense Power Up (Michaelangelo): MSRMM
Change Sound Effects: SMMRS
Power Up Effects Double (Raphael): SLDSM/MSLLR
Power Up Effects Double (Donatello): DMDRS
Power Up Effects Double (Michaelangelo): MMSLR
Power Up Effects Double (Leonardo): LSLSR
Unlimited Fire Shurikens/All Food is Pizza (Michaelangelo): DRDSS
Unlimited Shurikens (Leonardo): SMRDM
Unlock Playmates Toy Data Base: LSDRM
Unlock Splinter for Story Mode: MSRLS
Change your system's date to either December 24th or 25th to see the turtles in Santa garb. Change it to October 31st to wear a pumpkin on your head.
Put in this password on the options menu: R R L M D. (To use this costume, hold L1 or R1 when selecting Michaelangelo.)
Beat the third Dojo Stage with all four turtles to learn the Secret of Gembu maneuever. Use the move to damage everyone on the screen. You'll have three opportunities per level to use it.