Merlin, in Arthurian legend, magician, seer, and teacher at the court of King Vortigern and later at the court of King Arthur. He was a bard and culture hero in early Celtic folklore. In Arthurian legend he is famous as a magician and as the counselor of King Arthur. In Tennyson's Idylls of the King Merlin is imprisoned eternally in an old oak tree by the treacherous Vivien (or Nimue), when he reveals the secrets of his knowledge to her.

or pigeon hawk

Small blue-gray falcon (Falco columbarius, family Falconidae), with a narrowly white-banded tail, found at high latitudes in Canada, the western U.S. south to Colorado, the British Isles, Scandinavia, and Iceland. Most migrate to just south of the breeding range, but some go as far as northern South America. The merlin inhabits wet, open country or conifer and birch woods. It usually lays its eggs on the ground in bushes, but may occupy an old rook or magpie nest in a tree. An aggressive hunter, it was once much used in falconry.

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Magician and wise man in Arthurian legend. In Geoffrey of Monmouth's History of the Kings of England, Merlin was an adviser to King Arthur, with magical powers that recalled his Celtic origins. Later narratives made him a prophet of the grail and gave him credit for the idea of the Round Table. In Sir Thomas Malory's Morte Darthur he brought Arthur to the throne and served as his mentor throughout his reign. His downfall was linked to his infatuation for an enchantress, who imprisoned him after learning the magic arts from him.

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