Atticus found some kind of magic mushroom, ate it, and turned into a piglet.

Dialogue

A: The princess is gonna eat us B-dog!
H: But we have sharp teeth because we're dogs!
A: And scratchy fingers!
H: Scratchy fingers like tigers!
A: WE HAVE SHARP TEETH AND SCRATCHY FINGERS LIKE TIGERS

The princess is dispatched in short order.