The Specters all revive each other. The Specters also shoots Damage Walls. You have to clear all the Specters in one shot to break the loop. The Specter's weak point is in its center. You need Pierce monsters to hit the weak point and to easily clear the Specters. The Demons have a powerful Volatile Blast that deals 44000 damage. Defeat the Demons before they shoot their Volatile Blasts.