Helake, Helius, Helyus
One of the two peasant brothers who were protégés of King Armant of the Delectable Isle and the Red City. They treacherously killed the king and seized his kingdom. Palamedes killed Helain and avenged King Armant’s death.
Helain is first found in the Prose Tristan, where his brother is unnamed. Malory gives variations of the name – Helake and Helyus – to both brothers. In La Tavola Ritonda, Helain is called Passauver. His name is a variation of Alain, and the spellings are interchangeable.
Sources
Prose Tristan | 1230-1240
Le Morte Darthur | Sir Thomas Malory, 1469-1470