Xyor

Xyor, the Unwed is a Hive Wizard Major who appears in a special instance of The Summoning Pits that is only available during the the exotic weapon bounty A Light in the Dark. Xyor spawns with the third Tombship during the battle with Phogoth. In order for her to spawn, enough enemies must be killed to spawn a third Tombship, and Phogoth must still be alive.