Sethir the Ancient

Sethir the Ancient was a satyr located on a branch of the new world tree Teldrassil, north of the Oracle Glade. Sethir was one of the few satyr who is considered to be humanoid. This was most likely to enable the picking of his pockets for the completion of a quest.

The objective of the quest Destiny Calls was to steal Sethir's Journal from him without him noticing it.

Attacking Sethir would cause a lot of Minion of Sethir to appear, making it difficult to retreat back onto Teldrassil without taking heavy damage. It was therefore not advisable to attack Sethir unless you had good backup, or fast feet. Stealthing and pickpocketing was the most advisable route, as it was almost impossible to kill him with his minions. Sethir the Ancient could also teleport so one had to be quick about pickpocketing. However, when he stopped at the end of the smaller branch, he could be sapped, pick pocketed, and then killed with none of his minions spawning.

Speculation
It is unknown if Sethir survived the Burning of Teldrassil.