Hint: Speak with Crowhood the Olden at -2631, -396, -2104 . This is North East-ish of the Bellywhumper burrows. She tells you a slimy thing has stolen her medicine bag.
Inspect the tomb close to the 4th totem, 4 lvl 83 heroic will spawn and aggro. You must be able to speak Ykeshan to read the tomb. After killing them a named lvl 84^^^ Incuuba will spawn, kill him.
Mizzog tells you to create something to protect your mind (four items and a medicine bag to carry them) and provides you with a list of ingredients, a recipe and a sewing kit. If you lose one of them, the box next to Mizzog can be harvested to receive those things again.
Head back to the grave at 180, 87, -417 , and talk to Shulatu Darkscar, a ghost, who will ask you to subdue eight animal spirits. The animal spirits are located all around Kunark and require you to use the spell Spirit Sight, (Defiler Spirit Sight), which Shulatu will give you. All of them should have a knockback and stun. They are single-player mobs but level 84, so it won't hurt to at least bring one other person with you. They roam in circles about the following locations:
Tiger - Kunzar Jungle around -202, 115, -336
Gorilla - Kunzar Jungle around -471, 12, 124
Chokidai - Kunzar Jungle around 652, 98, -646
Shark - Fens of Nathsar around -1777.74, -448.15, -2992.21
Cockatrice - Fens of Nathsar around -259, -83, 1372
Crocodile - Fens of Nathsar around -135, -408, 949
Rhino - Jarsath Wastes around 632, -45, 681
Wyvern - Jarsath Wastes around -2108, 175, 1373
Return to the grave, start the ritual (click on the mound). Bring a group, because after Shulatu's speech, a series of heroics will spawn (2 waves: of 3 and 4, 83^^). Kill them and Shulatu Darkskar's ghost (84^^^). Accept the rings.
Return to Mizzog. She wants you to find a strong spirit.
Your Mythical Weapon has unique effects which will not work on level 81-90 spells, combat arts, or pets. By completing two quests, you may convert your Fabled or Mythical Epic Weapon into an Enervated Weapon and add persistent Mythical Effect spells to your knowledge book. This allows you to acquire other weapons without losing class-defining Mythical effects.
The quest requires that your class and your Epic weapon match. You will only receive the mythical spell gem of your current class.
You can start this series as long as you have the fabled version of your epic. But if you have completed "Epic Repercussions" then you will not be rewarded the mythical weapon if you go back and complete your class specific Kunark mythical quest.
The quests which make your Epic Weapon effect into a spell is the same for all classes.