Considered by many to be the most dangerous beast in existence, the Nundu is a gigantic leopard, native to East Africa, whose breath carries disease and death. Whole villages have been wiped out by the creature, and it takes a hundred wizards working together to overcome the beast (FB).
When the Nundu roars, a lion-like mane bursts forth from its neck (WFT).
A wizard thief by the name of Eldon Elsrickle brought a baby Nundu with him from Africa to London. The creature eventually grew large and deadly and killed the thief (BoS).