Invincibility
Pause gameplay and press Left, Left, Right, Right, Up, Up, X.
All Creatures
Pause gameplay and press Left, Right, Left, Left, Right, X.
All Multiplayer Levels
Pause gameplay and press Left, Right, Left, Right, Up, Left, Right, X.
Mark All Objectives Complete
Pause gameplay and press Left, Right, Right, Down, Up, Down, Down, X.
Crystal
Pause gameplay and press Left, Right, Left, Up, Right, Down, Left, X, X.