Board Thread:Lore Discussion/@comment-6702118-20140722142914/@comment-25260217-20140803130107

Alduin is more powerful than Dagon. Dagon cannot be killed outside of Oblivion, while Alduin can only be defeated by Dragonborn. And please note that Dragonborn is not ordinary mortal. The Dragonborn has the soul of Dragon and a body of men.