Artemis' Bow belongs to the goddess of the hunt, Artemis. It has the ability to change humans and gods into animals and vice versa. Autolycus once stole the bow and then sold it to Discord who used it to transform Hercules into a pig. Later, Iolaus used it to turn Discord into a chicken (HTLJ "Porkules").
When Katherine told Hercules she wished she were human, Aphrodite used the bow to grant her wish. Later, she reversed the change at Katherine's request (HTLJ "One Fowl Day").
Gallery
In "Porkules"