Exarch

"Before Malthael turned, his sages of wisdom occasionally reached an exceptional level of knowledge that granted them the title of exarch. These esteemed followers would guard the Chalice of Wisdom when Malthael was away, and they were the last to leave after their master disappeared from the High Heavens."

- Lorath Nahr

Exarchs are fallen angels in the Reaper ranks, encountered only in the very end of in Diablo III.

In-game
Exarchs are only encountered in Pandemonium Fortress and Nephalem Rifts. They are caster enemies, much like Morlu Incinerators.

While they have a melee attack (in form of the cone of lightning that knocks enemies back), Exarchs try not to engage in combat with the player, moving away from the enemy quickly if given a chance. Instead they summon huge Lightning orbs that strike the large area with Lightning charges for 5 seconds, dealing increasing ticks of damage to everything within their effective range. These orbs' areas overlap, stacking damage infinitely.

A single Exarch is nearly harmless, but a bunch of them, especially if assisted by Anarchs or Executioners, can make heroes' advance much more difficult. Before the orb starts dealing damage, there is a very brief delay, so with relocation skills, one can leave the area of effect in time.

Uniques

 * Celik (Pandemonium Fortress Level 2)
 * Hyadures (Pandemonium Fortress Level 1)
 * Judge Alzarius (Pandemonium Fortress Level 1, Judgement event)
 * Paolillus (Pandemonium Fortress Level 2)
 * Valtesk the Cruel (Pandemonium Fortress Level 1)

Subtypes

 * Prison Warden