Sir Kay

In Arthurian legend, Sir Kay /ˈkeɪ/ (Welsh: Cai, Middle Welsh Kei, or Cei; Latin: Caius; French: Keu; French Romance: Queux; Old French: Kès or Kex) is Sir Ector's son and King Arthur's foster brother and later seneschal, as well as one of the first Knights of the Round Table. In later literature he is known for his acid tongue and bullying, boorish behavior, but in earlier accounts he was one of Arthur's premier warriors. Along with Bedivere, with whom he is frequently associated, Kay is one of the earliest characters associated with Arthur.

Cai or Cei is one of the earliest characters to be associated with the Arthurian cycle, appearing in a number of early Welsh texts, including Culhwch ac Olwen, Geraint fab Erbin, Iarlles y Ffynnon, Peredur fab Efrawg, Breuddwyd Rhonabwy, Pa Gur yv y Porthaur and the Welsh Triads. His father is given as Cynyr, his son as Garanwyn and his daughter as Kelemon.

Before Cai's birth, Cynyr Ceinfarfog prophesied that his son's heart would be eternally cold, that he would be exceptionally stubborn and that no one would be able to brave fire or water like him. Cai is attributed with a number of further superhuman abilities, including the ability to go nine days and nine nights without the need to breathe or to sleep, the ability to grow as "tall as the tallest tree in the forest if he pleased" and the ability to radiate supernatural heat from his hands. Furthermore, it is impossible to cure a wound from Cai's sword. Cai is killed by Gwyddawg fab Menestyr, who is in turn killed in vengeance by Arthur.

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