Yeah, it's not that hard of a map, it's just that if you don't have any of the plat gacha pirates then suddenly you're in the rare situation where witches can shine for once. Basically, you'd rather have physical ranged dps more than anything else for the vast majority of the map but scorpions are custom designed to no sell any physical attack under a thousand damage. That's where witches come in--there's no need to overreact and spend a ton of UP on mages because there's only 4 scorpions to deal with and even Calliope can squish one in four shots so that your vampire hunters and archers can go back to smashing everything else.