Mike Tyson Heavyweight Boxing
When “Press Start” appears at the title screen, press:
Master code – Square, Circle, L2, R2.
All created boxer items – L1, R1, X(x2), Triangle, X.
Random sized boxers – Square, Left, Up, Triangle.
Big heads – Square, Circle, Up, Down.
Small heads – Square, Circle, Down, Up.
View full credits – X, Triangle, Square, Circle.