Orchendor

Orchendor is a powerful mage encountered in the quest The Only Cure.

Quest
Orchendor was a priest of Peryite, aiding him in spreading disease and creating the Afflicted. He eventually decided to cease working for the Daedric Prince, which prompted Peryite to seek the Dragonborn's help in ridding Nirn of the unfaithful priest. He resides in deep withing Bthardamz.

Tactics
Orchendor utilizes standard destruction spells, favoring frost. Do not underestimate his staying power, however, as when cornered or sufficiently injured, he will teleport (becoming momentarily invulnerable) to a nearby space or even to another tier of the same room. In addition, Orchendor is able to resist many Destruction spells, up to about Adept-level spells. As a result, weapons (such as Bound Swords) are recommended.

If the player can make use of the Dead Thrall spell, Orchendor is an excellent reanimation candidate and one of a few very powerful Thrall Options.