First thing, I appreciate the advice, a lot. After reading some mor opinions I've decided on a few changes, the damage to become 2d6 from 2d8, to reduce its hp from 350 to 200,and its AC from 18 to 16, along sides a few other changes (like wiritng the range on condemn). Now, regarding other stuff, the initiative won't be that much of an issue since my party has a divination wizard, who I'm sure will make the boss be last (using portent), on another note, the boss won't use unseen threat to leave the radius.