Enter SRMLDDR as a password.

Enter SDSDRLD as a password. You will lose all health after falling. Note:
This code has no effect in the tournament modes.

Enter RDSRMRL as a password. All enemies will have their defense doubled.
Note: This code has no effect in the tournament modes.

Enter DSRDMRM as a password. Your character will always have full health.
Note: This code has no effect in the tournament modes.

Successfully complete level 11-7. Alternately, Splinter is unlocked ten days after a saved
game file is created; you can change the system date to do this. Splinter replaces
Donatello.

Got to level 9-1 and get the hidden Antique. Do this by going down one of the
alleyways. There will be a pile of crates and a broken down bus. Jump on the crate and
onto the bus. From the bus, jump onto the building . There should be two crates here,
containing Pizza and the Antique. Then, complete the level and defeat all the Purple
Dragons, Foot, and Mobsters. Next, go to the " 2nd Time Around". If you look through the
different objects in the "NY" section, you will see the image of an arcade. Select the
arcade to see information on it. When you exit out of the information, the message
"Classic Arcade Mode Unlocked" will appear, and that option is now on the main menu at the
title screen. Note: Do not worry if the screen remains black, or the arcade main
screen takes a long time to load; this is normal.

In the arcade game, press Circle to get more lives instead of quarters. The joystick
and certain buttons including the pause feature do not work. The character selection is
just like the arcade. Each controller controls a different turtle. You cannot choose which
turtle to assign to a controller. Controller one is Leonardo, controller two is
Michaelangelo, controller three is Donatello, and Controller four is Raphael.