The Corrupted Empress

If we know the length of Pot cooldown we could overcome it with this.

Evan's Mana aura skill + Bishops heal in every party keeps everyone alive during the pot cooldown

She can apparently zombify. So the only solution for some healing is the Mechanic one, Healing robots(20 MP 50; 40 second summon duration, H-LX heals 25% of max HP, 400% selfdestruct damage / 45 second cooldown). And I'm thinking these skills might be useful, Satellite (MP 40; 160% damage, summon up to 3 satellites), and Safety (Satellite attack damage increased by 50% / Triggers when attacked for more than 30% HP in damage, absorbs 80% damage / Cooldown time: 10 seconds), cd 9 secs with combat orders. I might be wrong with this, but its possible that only 1 Satellite out of the 3 u can summon is destroyed after absorbing a total of 80% dmg, so you have 3 satellites there that protects you and a CD of 9 seconds with combat orders. With threaten the 37k m.atk goes down to 25.9k, with Safety, Mechanics will take 1/5 that dmg, a bit less than 5.2k. Healing robots might be able to heal that dmg. And Mechanics have rush, so they can take damage and heal themselves enough hp to survive pot cd and zombify, and rush the monsters keeping the party alive. Of course, this is only if Safety works that way. I haven't considered other dmg reduction skills such as Combo Barrier, Evan's shield, and Blue Aura. Those might help even more.