Update: Due to feedback from the players, the developer has substantially increased the boss spawn rate. So it should be a lot easier now. The Emperor protects!
If you are playing Warhammer Inquisitor as I do, you probably would wonder how long it would take to complete season 6. To answer that question, I would look at probably the lengthiest objective to complete, which is Ultimate Escalation.
Ultimate Escalation requires us to take down all 10 unique seasonal bosses. Each seasonal mission requires escalation points to generate and escalation points culminate as we take down Harbingers. Each seasonal mission we generate has a 15% chance to spawn a seasonal boss of a random type. Depending on how fast you can fill up the escalation bar – which in my case is somewhere between 30 mins to 1 hour including the actual gameplay, inventory management, screen loading time, etc., you can work out an estimation on how long more to go.