All characters and levels:
At the BoomBot selection screen, press Square, Square, Square, Square, Circle, Circle, Circle, Circle, Square, Square, Square, Square, Select, Select, Select.
Cheat mode:
At the BoomBot selection screen, press Square, Circle, Circle, Square, Circle, Circle, Square, Circle, Circle, Square, Circle, Circle, Select, Select, Select to enable cheat mode. Then pause the game and enter the following codes:
One-hit kills CPU opponent: Circle + Square + Triangle
CPU opponent has 100 health less: Circle + Square
