Disclaimer:I know we already had a Fallen based expansion but we also have had two hive based ones. The idea is that we go against a fallen that's a vandal(not Variks) that turns from vandal to captain and captain to kell(or an archon priest). And we always try to stop him and the Fallen "rituals" to make him a bigger foe, and of course we fail so he can become stronger. Finally,the raid, so we travel either to the Fallen main world or to a giant Fallen warship(kind of like the Hive's Dreadnaught) we see him become a forgotten tier of Fallen higher than that of a Kell and an Archon. We stop his high guards as the small bosses(like Golgoroth, Warpreist, and Deathsingers in King's Fall) and this will lead us to the main antogonist. The reason I made this was because I would like to see how fallen change from low tries to high tiered officials in the Fallen lifestyle. Also we can get even more backstory on them as well Feel free to discuss ideas of the bosses and other things like the missions in the comments.