Unlimited ammunition
Press B , X , B , Y , A , X , A (2) at the title screen.
Unlimited health
Press A , B , A , Y (2), X , B , Y at the title screen. Once you or a CPU dies, your/their health bar replenishes to the maximum.
All arenas
Press Y , B , Y (2), A , X , B , X at the title screen.
All costumes
Press B (2), A , X , B , Y , A , B at the title screen.
Play as Butch
Successfully complete challenge mode as Tyke.
Play as Ducking
Successfully complete challenge mode as Nibbles.
Play as Eagle
Successfully complete challenge mode as Duckling.
Play as Lion
Successfully complete challenge mode as Butch.
Play as Nibbles
Successfully complete challenge mode as Spike.
Play as Spike
Successfully complete challenge mode as Tom.
Play as Tyke
Successfully complete challenge mode as Jerry.
Play as Monster Jerry in multi-player mode
Successfully complete challenge mode as Lion.
Play as Robot Cat in multi-player mode
Successfully complete challenge mode as Eagle.
Secret courses
On tournament or quick game modes, go to team battle and place players one, two, and three on team "A" and player four on team "B". Choose these players. First Spike, then Tom, then two Jerrys. You will now have access to the Some Like it Hotter and Raging Mouse courses. If you want to play these again, repeat the steps. Note: All players have to be human (four controllers used).
Secret weapons
On Lungens And Dragons, hit anything that can be destroyed. When it says "Map destroyed", look for the sword in the rock to find the secret weapon. The same can be done on all levels for different weapons. Note: If you use Jerry, Nibbles. or Tom, you may get a costume on Lungens And Dragons. On the western level, you can unlock a costume with Tom, Nibbles, and Spike.