Ancalagon the Black

[Zigûr]

Originally Posted by Aster

Assuming that they were more successful/Melkors commandment was more clever, what would have happened after his victory?..
I agree that he could not destroy everything, sure. He himself became part of Arda.

This is another interesting question. I think we can see two ambitions composing Morgoth's character at the end of the First Age:

1) the desire to be an incarnate King/Tyrant over Middle-earth if not all Arda.

2) "nihilistic madness": his irrational hatred of all life and matter.

"Morgoth had no 'plan': unless destruction and reduction to nil of a world in which he had only a share can be called a 'plan'." (Morgoth's Ring)

So I think he would have tried to conquer Arda, find himself unsatisfied and then try to destroy it, but the matter of dealing with the Valar is obviously a substantial one. He could perhaps have waited and re-absorbed a lot of his dissipate potency into himself, which I believe Professor Tolkien speculates he could have done, and then attacked Aman, but I feel as if the failure of the Host of the West might still have only resulted in an ongoing stalemate if it didn't result in a direct confrontation between Morgoth and the Valar in which Arda would be severely damaged if not destroyed.