Questing Beast

"At the very heart of the Old Religion lies the magic of life and death itself. The Questing Beast carries that power. One bite, you die, and there is no cure."

- Gaius

The Questing Beast is a deadly creature with the magic of the Old Religion that inhabits the land of Albion. It has the strong body of a leopard and the fearsome head of a snake. Its venom is highly poisonous, where one bite means assured death and there is no cure. Only the Old Religion can bring such an injured person back to life, by sacrificing another in their place.

History
The beast played an important role in the Old Religion as it is regarded as a terrible omen. It has appeared on at least two known occasions - the death of Queen Ygraine which had caused the Great Purge, and once again twenty years after. The beast bit Arthur resulting in his near-death; he is only saved when Merlin goes to the Isle of the Blessed to sacrifice his own life for the prince. It is uncertain whether the beast had appeared as a portent for Arthur's near death or for another reason (Le Morte d'Arthur).

Legend
The Questing Beast, whose more physically descriptive French name is the "Beste Glatissant" or "The Barking Beast," has a leopard body, a serpent head, a lion's hindquarters, and rabbit's feet. A noise like the barking of a hound pack issues from its stomach. The Questing Beast appears in the Arthurian legends as a powerful creature sought after by King Pellinore. According to Merlin, the beast was born of a woman who tried to seduce her brother but was manipulated by a demon to lie with him and accused her brother of rape. The beast itself is an omen for violence, incest and chaos. The beast appears twice to Arthur; first after he (unwittingly) sleeps with his sister Anna (or Morgan le Fey in later adaptations), and secondly after he has a dream foreseeing the destruction of his kingdom by Mordred.

Trivia

 * Only one Questing Beast may exist at a time; when the current Questing Beast dies a new one will come into existence. A new Questing Beast may have appeared after Merlin killed the current one. However, the whereabouts of the new one were never revealed.
 * The Questing Beast is composed of a snake and a leopard. This version is composed of a cobra and a leopard in the first half with a white leopard in second half.