Earthworm Jim

Cheat mode:
Pause game play and press Left + A, B, X, A(2), B, X, A, Start. An option and information screen will appear allowing cheat mode (invincibility), level selection, pausing without a dim screen, or viewing the entire level. Note: Enabling this code may prevent completion of the game.

Invincibility:
Pause game play and press A + B, A + X, X, A, Left + A, Right(2), Left.

One time Mega Plasma Shots:
Pause game play and press A(2), B + L, A(2), X, B + L, X.

Mega Plasma Shots:
Pause game play and press A + X, B(2), A(2), X, B, L + R.

Level skip:
Pause game play and press A, B, X, A, A + X, B + X, B + X, A + X. Resume game play to start at the next level.

Wrong cheat code:
Pause game play and press Y, A, B(2), A, Y, A, B(2), A.

One time extra continue:
Pause game play and press A, B, A, B, X, Y, X, Y.

Extra continue:
Pause game play and press X + Y, B, Y, B, X, B, X(2).

Full ammunition:
Pause game play and press A, B, B + L, B, X, A, X(2). Alternately, press A + X, B, A, B, X(4).

One time extra life:
Pause game play and press B(2), A, X + Y, A(4).

Extra life:
Pause game play and press B + X, B(3), A(2), X, A.

Jump to Princess:
Pause game play and press Left + A, X(2), X + B, X, A, X, Left + A.

Full energy:
Pause game play and press A + X, B, A, B(2), X + Y, B, A.

Map view mode:
Pause game play and press A, X, A, X, A(4).

In-game reset:
Press L + R + Select + Start during game play.

Level codes:
Pause game play and enter one of the following controller actions to jump to the corresponding level:

Level

Code

What The Heck

Press Y, X, Y, X, A, B, A, X

Down The Tubes

Press Up, Down, Left + Down, Left, Down, Down, Up + Left, Down

Snot A Problem

Press A, B, X, B, A, B, B, B + L

Level 5

Press A + B, B + X, X + Y, Left, Left, Right, Left, Right

For Pete's Sake

Press A, B, X, A, B, X, A, B + R

Buttville

Press A, X, Left, Left, X + Y, Up, Down, Left

Andy Asteroids

Press A + L, A, R + A, A, B, B, X, B

Who Turned Out The Light?

Press A, B, Up + Y, Up + Y, Left, Right, Left, Right

Hint: Skip the snowman fight:
In the "What The Heck" level, proceed normally until reaching the first lawyer. If Jim has a megablast, use it to blow away the layer. Then, use the whip to reach a small spike below the ground level, and just to the right of the gear-like object. Grab the spike to reach the part where stalactites are falling, after the snowman fight.

Hint: Extra life:
In the "New Junk City" level, play until reaching the first set of tires that can be jumped upon. Go to the top of the tires and jump on the two platforms. Hold the flying power-up over Jim's head and start to glide. At the very last second, jump off and use the whip on to the moose's antlers. Jim will be thrown on some chains. Proceed ahead and watch out for the dogs. Jump into the towlet that appears to reach a screen with some super guns. After that, move to the left side of the screen and walk through the wall to receive an extra life.