Unlock Pitfall II: Lost Caverns:
Hold L R and press Left, Right, Left, Right, Y, Y, Y
Play as Nicole:
Hold L R then hit LEFT, UP, DOWN, UP, B, UP, UP.
Unlock Pitfall II:
Gather and use alls of the idol.
Bottomless canteen:
Hold L R then hit LEFT, X, B, DOWN, X, A, X, B.
Play as Retro Harry:
Hold L R and press Y, Left, Down, X, B, Y(2), Left at the title screen. A message will appear to confirm correct code entry.
Unlock original Pitfall:
Hold L R then hit B, B, LEFT, RIGHT, B, X, A, UP, B.
Hyper Punch Mode:
Hold L R then hit LEFT, RIGHT, B, UP, B, RIGHT, LEFT.