Hastur's new ability is that when you're devoured or insane in Arkham , the terror level increases by 1.
During final combat, are you considered to be in Arkham? I don't see why you wouldn't. Hastur is arriving to Arkham and you're meeting to stop him. You may not be definitively in a street or location , but you should still be in town . What's your take on this?
Also, during final combat, if you're driven insane, you're devoured. Does this count twice towards his terror trigger?
This became particularly important during tonight's game because a sufficiently high terror level would have resulted in doom tokens being added to Hastur—not to mention that terror-based Epic Battle card.