in the reveal stream we can see scorn in the throne world at around 1:20:33
obvious implication is they're going to be involved in the story in some capacity
since we already got 3 hive raids with crotas, kings fall, and crown of sorrow, im guessing the raid will focus on the scorn instead, with possibly fikrul himself as the final boss
Apparently the raid will take place in the pyramid where something ancient has been locked away waiting. The pyramid is also blown open in some places.
My theory is the ancient thing is what gave Oryx the power to take and is what has tasked Xivu Arath to pursue Savathun. I think "that" and Xivu Arath will be the final boss.