Tom and Jerry

Unlimited mice

Press Right(2), Up, Left, Up, Right, Down, B, A, Select, Start(2) at the second title screen (where Tom and Jerry are displayed in sunglasses).

In-game reset

Press A + B + Start + Select during game play.

Hint: Extra lives

Use the following trick to earn up to nine lives. In level 2 (Pipes), keep shooting the sleeping crabs which never move. At 50,000 points, you will get one bonus life. Repeat for more lives. You can do the same thing in the fire level by getting the spitting can and shooting the fire continuously.

Hint: Skip World 3 Stage 1

You can skip most of World 3 Stage 1 (rooftop). The first hole that you encounter (and leads to most of the stage) is too big to jump over. However, a leaf flying from the left side of the screen to the right can carry you across the hole.