Maw of Souls is a dungeon whose entrance is located in Stormheim in the World of Warcraft game. The minimum level for this dungeon is 110. The dungeon contains 3 bosses. The end boss of Maw of Souls is Helya.
Maw of Souls has a small number of bosses, three to be precise. Part of the action takes place on the mainland but mostly at Sea. The first boss, long dead King Ymiron who you killed in Utgarde Pinnacle makes a return as an undead king hoping to kill you again and quite naturally failing. This is the dead opposite to the Halls of Valor, where the greatest warriors go when they die.
The first part of the dungeon takes pace on the mainland where undead Vrykul warrior await the Nagifar, a fearsome ship made of bone and sinew (tendon or ligament). From there the undead warriors travel to Helya who will "look after them for the rest of eternity. The dungeon is based on Viking legend, the final boss is based on the Viking legend Hel who was a viking goddess who would ensure their damnation. The second part of the dungeon is based on board the actual ship. There is a lot of trash on both ship and land so be ware, not all trash needs to be killed.
Poor old Ymiron, he was once leader of the Val'kyr on the northern Azeroth kingdom of Northrend until he was deposed by you in Utgarde Pinnacle and killed. He is now a lackey for Helya in her underworld.
When you first encounter him, clear all the trash before taking him on, its a lot easier that way. He is easy to kill. You need to look out for the aoe damage he puts on the ground and the push back he does on your players but apart from that, there's nothing to worry about with this boss.
After you kill him, one of the players must blow the horn so you all can be transported onto the Naglfar, a ship that is made from bone and sinew (tissue connecting muscle and bone). The material is from the dead who had fallen out of favour with Helya. When arrive on the Naglfar, you are in cages that can be clicked on to open.
Harbaron is the ferryman, the man whose job it is to pilot the Naglfar to the final resting place of the dead. It is a character that is based on old Norse legend. The original norse character is called Harbarth (Latinised) ref: Sacred Text.
The main thing is that he will create shadow versions of your characters which walk away from you. You must dps these down as quickly as possible. Unlike the final boss of Temple of the Jade Serpent, these don't fight you but if they get too far away from you, they will cause damage.
This will be the second time you'll have faced Helya if you have done the entire Stormhelm quest line. After having despatched the ferryman Harboron, and the trash, you now face Helya. You will not be able to kill her, just damage her a little bit so that decides to retreat and you get your rewards.
The first phase will be her tentacles which are wrapped around the ship. Simply dps these tentacles down so that she eventually gives up. After you hurt her, she'll disappear but not for long. The very front of the ship will be broken off and she'll be closer to the ship
She'll pierce the ship with tentacles which will cause knock back so be aware of this when it happens. The tentacles don't last for too long. During the battle, she'll blow water on the ship where you'll need to them move out of the way otherwise the damage will hurt you.