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
'Ancient evil' sounds like a unique enemy to me. My first thought was one of the Worm Gods - whichever one Savathûn answers/answered to directly - but seen as it's an actual pyramid ship, I can see it being a Darkness entity.
There has been increased dialogue about the being behind the darkness this season, so I imagine we'll see something related to them.