An Erumpent
'Weighing up to a tonne, the Erumpent may be mistaken for a rhinoceros at a distance... The Erumpent’s horn can pierce everything from skin to metal, and contains a deadly fluid which will cause whatever is injected with it to explode. Erumpent numbers are not great, as males frequently explode each other during the mating season.' – Newt Scamander
Photo courtesy of Warner Bros. Pictures