We don't have a full walkthrough for this zone, but here's some tips for the more difficult mobs.
Seer Gh'char in Realm of Proof: Hide behind a dragon statue (one in back of him is best) when you see a message that he ports to the center and prepares to unleash destruction. You will be informed when you are able to be hidden from sight and be able to avoid the damage. Mercenaries are trickier here and may not survive it. Other option is to try to burn him down before he gets the chance to finish his spell. There is a wandering named nearby, may want to clear him first.
Ashlok Cenobites around the Temple of the Great Devourer: If they complete their meditation they will go berserk, heal to 75% health and dish out a lot of damage.
Prime Magnate Mrelgt, final named at World's End: This mob can enter a challenge mode. Purple text will state that he "begins to gather darkness around him! (challenge)" If you want to interrupt this, click on him (should be a hand icon) ASAP. If you get the message that "Mreglt plunges you into eternal darkness!" then challenge mode has engaged and he will fully heal and turn into a ^^ mob that dishes out very heavy damage. He will updated the quest Shades of Drinal: Puzzle Pieces.
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