User blog comment:Mythicdusk/Possible Skyrim DLC?/@comment-69.205.32.99-20120123074231/@comment-64.222.174.191-20120124023303

There's a few underwater dwarven cities, and shiprwrecks. And there's a quest where you must fight animal spirits, including many of the animals you just listed (like a giant mudcrab). I think it's called Kyne's trials or something.