did Mehrunes Dagon Die?

Is he still a Daedric Prince?

What happened to him after the fight with Martin?

He was sent back to Oblivion, yes he is still a Daedric prince. He was bitten by the Avatar of Akatosh and was "killed" in the mortal realm thus being sent back to Oblivion, he is alive in his own realm but he cannot come back to the mortal realm.

I think you're right about that. I think we can safely assume that, yes, Mehrunes Dagon still lives, just that he was banished from Nirn and sent back to Oblivion. And since as I understand it, the dragon statue that the avatar of Akatosh became pretty much replaced the Dragon Fires as the thing maintaining the barriers that protect the mortal realm from Oblivion, he shouldn't be able to invade again, at least not in the near future, though being the Prince of Destruction, I'm sure he'll find more ways to cause trouble in the future. And I'd imagine that he'll be back to giving tasks to heroes who find his shrine and rewarding the, if they complete him in Skyrim.

In any case, this probably belongs in Cheats, Hints and Spoilers, since what happens at the end of the main quest is probably a pretty big spoiler...

We could tell you, but then we would spoil Elder Scrolls VI... :tongue:

Agree with the above. To my knowledge he cannot be destroyed. He can only be banished from Nirn (or Mundas) presumably to his own planes of Oblivion. It seems likely that this is not the last time he'll appear in an Elder Scrolls game. Maybe he'll even make a guest appearance in Skyrim.

In general Daedric Princes and the Nine cannot be destroyed. Notice what happened to Jyggalag, most of the other Daedric Princes ganged up against him, and still couldn't destroy him. Lorkhan is a somewhat odd case, what happened to him is a bit unclear to me. But the Lore forum people could probably give theories.

But the fight in TES IV was just with his avatar, and only his avatar was destroyed and his access to Mundus cut off.

Lorkhan isn't really dead as in "everything about him stops functioning", his Heart was very much alive and can kick some bottom (don't know about now)

Lorkhan's heart desired the world so badly that he convinced the Aedra to create Mundus...

After the world was created the Aedra permanently bound Lorkhan to the object of his affection Nirn

They did this by ripping out his heart and making it essential to the world it desired so much.