He will send you to recover 5 rotten fish barrels to feed the Leviathan. They are small harvestable buckets located right where the river meets the ocean and do respawn.
Head to Chelsith and speak with Uguaz Tysk( -9, 5, 398 ) at the beginning of the zone. You need to speak Goblish.
You must destroy 4 idols. These idols are found at the Upper Tier Named random spawn areas (statues of Frogs etc...). Simply stand behind the altars and activate the rock crusher. You must have the Rock Disassembler equipped in order to use it.
Kill 75 Reet slaves in Sebilis - either near sporconids on lower level or near labs on upper level (look for orange dots on your map when you get close).
Kill Commander Jorah in Karnor's Castle (His placeholder does not give the update). He's located in the Commander's Chamber, upstairs.
The zone in to the instance where the final mob (82^^) is found is in front of where the Avatar of Hate spawns ( -1307, 48, -1509 ) . There is an anvil on the ground near that location, click it to zone into instance. (Only Inquisitors on the same step may enter the instance.)
Examine Xass's Notebook to start the quest for your Mythical Epic.
Return to the Skeleton of Yasva V'Alear to claim your Mythic weapon.
Level 90 Mythical Conversion
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.