As new Lorekeeper, the season finale, is not here yet, it’s speculation time!
I think new story about epic battle will set completely at Darkstone, with 2 new Khaziel troops joining force leaded by Halfgrim Half-Giant. The Three Dragon attempt to stop the new Blight might not be a complete success, and some sacrifices will have to be made for it. And somehow, the result of this battle will lead to the existence of Tower of Doom and its origin story in the lore. Why?
Tower of Doom’s background is very similar to Blight Land, the former Blight. Beside, those pyramid-shape rock floating on the picture is very similar to Darkstone’s island structure. So Torgan’s (The Possessed King) plan with Umbraxis might be the thing responsible for possible next Tower of Doom’s arc.