Isn't that the last dlc? If yes here's my theory. Since the cabal is the strongest enemy in the game(the taken might be more powerful)they go to invade every planet(there's already cabal on the moon on the pvp map cauldron) including the tower. A strike will be at the tower to kill the cabal that leads the team to destroy the tower. The raid will be at the city below the tower and your trying to save the traveler from the cabal God(his name is Valus) the story is filled with cutscenes of the cabal God destroying the city and hurting but not killing the speaker, in the end Valus damages the traveler very bad but you kill him after and there's a final cutscene of the stranger comes out and says her and her exo friends can heal the traveler. Since the traveler is damaged you are less powerful and get 3 new subclasses with a new type of burn. and finally the raid, the objective is the heal to traveler. The raid is very long. You go to every planet and kill a bunch on enemies and a boss at the end. Every time you kill a boss in each planet you get a message from the stranger saying it is healing!! The reward for beating the raid in hard mode is getting a exotic khvostov(not 100%)