Level select

Press Up, Left, Circle(2), Left(2), Square, Down, Up, Circle at the main menu.

Level skip

Press Square, Triangle, Left, Down, Right, Triangle, Right, Up, X while playing the game.

Invincibility

Press X, Triangle, Right, Left, Circle, Up, Down(2), Right, Circle(2) while playing the game.

Extra damage

Press X, Triangle, Right, Up, Right, Triangle, Circle, Right while playing the game.

Burn everything

Press Square, Triangle, Left, Down, Square, Circle while playing the game.

Goat mode

Press Triangle, Right, Left(2), Circle, Triangle, Square, Right, Up while playing the game.