Hi guys. I have some predictions for the end of Legion.
Blizzard said that demons truly die in the Twisting Nether.
Here is how Legion is going to end:
7.2 - Defeat Kil'Jaeden and send him to the Twisting Nether, and kill the Avatar of Sargeras for the first time.
7.3 - Defeat Archimonde (again) on Argus and send him to the Twisting Nether, and kill the Avatar of Sargeras a second time.
7.4 - Travel to the Twisting Nether itself and kill Sargeras himself, destroying the Burning Legion, NEVER to be seen again. We find Medivh* there relieved of Sargeras' corruption, and Illidan dies**.
In between those major patches we are going to have other raids and new dungeons.
*Yes, Medivh is still alive.
**Not really dead, he has an immortal demon soul.