Input this code at the main menu to be invincible or skip stage.
To enter multiple cheats, enter the code, but instead of starting the game, enter the Music/Sound test menu then exit it. Do this to activate both the level select and invincibility codes, then press Left, Right, Left, Left, Left. Now start a new game, and instead of playing as Daffy Duck, you will be playing as Fergus McGovern's (the founder of Probe) head.