The Erumpent is a huge African magical beast resembling a rhinoceros. It is a powerful creature, with a thick hide capable of repelling most curses and charms, a single long horn, and a thick tail. They are treated with great caution and respect by African wizards and witches.
The Erumpent will not attack unless provoked, but the results are usually fatal. The horn can pierce skin and metal, and the horn contains a deadly fluid which causes whatever is injected with it to explode. There are apparently rare occasions when the injected object or being does not explode, as in the case of Wilfred Elphick, first wizard to be gored by an Erumpent. As his Chocolate Frog Card depicts him in bandages, but very much alive, it can be assumed that he survived the attack and did not explode.
Erumpent numbers are not large, because male Erumpents frequently blow themselves up during mating season. Erumpents only give birth to one calf at a time.
Erumpent horns, tails, and Exploding Fluid are all widely used in potions, although they are listed as Class B Tradeable Materials. At some point, Xenophilius Lovegood acquired an Erumpent horn and kept it in his house, believing that it belonged to a Crumple-Horned Snorkack. When Harry Potter, Ron Weasley, and Hermione Granger visited him in 1998, Hermione warned him to get rid of it but Xenophilius maintained his ignorance and believed it to be a horn from a Crumple-horned Snorkack. When Harry, Ron, and Hermione realised that Luna was missing and Xenophilius was planning to trade Harry for Luna they tried to escape before the Ministry members Xenophilius had called could arrive. Fearing they would get away Xenophilius attempted to stun Harry, but instead he hit the Erumpent horn which exploded and blew up a sizable portion of his house.
- Harry Potter and the Philosopher's Stone (video game) (First appearance) (Mentioned on a Famous Wizard Card)
- Harry Potter and the Chamber of Secrets (video game) (Mentioned on a Famous Wizard Card)
- Harry Potter and the Prisoner of Azkaban (video game) (Mentioned on a Famous Wizard Card)
- Harry Potter and the Deathly Hallows (Mentioned only)
- Fantastic Beasts and Where to Find Them
- LEGO Harry Potter: Years 1-4 (Mentioned only) (Handheld versions only)
- Harry Potter Trading Card Game (Mentioned only)