Ultraxion's dead bruh. Besides, Galakrond's remains are in Northrend, Ulduar is in Northrend, the Sepulcher could be on Azeroth's moon or some shit, the Gardens of Life are available for us to explore likely, and Azeroth's Titan is right there...
Oh, and guess what...
Guess where Chromatus is...
IN AN ARCANE PRISON ON NORTHREND!
Listen, I just wanna fight em! Also, Me'dan may still be canon, but the Comic plot with him and the Guardian shit doesn't exist in the canon.
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If the next expansion of Light and Void based (Could be, could also be Light based only, who knows), the Dragon Isles NEED to the main leveling Continent, with the Undermine as a Dungeon, Farahlon as a megadungeon or patch-zone, Shattrath as a raid with Yrel and Lothraxion as the final bosses (Maybe AU A'dal?), and a Dragon Isles starter raid with the Infinite Flight, the Chromatic flight, and Chromatus as the final boss.
"Chromatus' five heads grant him the power of all five dragonflights"
IMAGINE!!!!!!