It is a possible corporeal form of the Patronus Charm. Seamus Finnigan's Patronus took the form of a fox and he used it during the Battle of Hogwarts in 1998 to repel several Dementors from himself, Harry, Ron, Hermione, Luna and Ernie. Seamus Finnigan has cast too his corporeal Patronus in the lessons of the Dumbledore's Army. But he focussed not enough and it vanished immediately.
- Harry Potter and the Prisoner of Azkaban (First mentioned)
- Harry Potter and the Half-Blood Prince (First appearance)
- Harry Potter and the Deathly Hallows
- Harry Potter Trading Card Game
- Pottermore (Appears as a Patronus)