Teenage Mutant Ninja Turtles 2 : The Arcade Game
Extra Lives without Stage Select
On the Title Screen, press Up, Right, Right, Down, Down, Down, Left, Left, Left, Left, B, A, Start
Stage Select
On the title screen press down on the control pad 5 times, then press right on the control pad 7 times, then A, B, Start.
Extra lives and stage select
At the Title Screen press B, A, B, A, Up, Down, B, A, Left, Right, B, A, Start