Sorry if I'm a bit late, but Maw of Souls is by far the most badass dungeon in this game.

Now I knew from the start that the level design and art team knocked it out of the park with Legion, but I just hit 110 and did Maw of Souls for my order hall and I my mouth was agape at the whole scene with the boat. The rocking sea in the background, the walking through a spooky ass ghost ship, and the fight with Helya.. it was all jaw droppingly metal as fuck. It literally made me fuzzy with adrenaline at how awesome it was.Good job Blizzard.