The reasoning on Rotom is that sand+bulk allows Ttar to live a hydro pump.
It isn't walled by quag because it's stronger lol. Quaq lives two Krook pursuits, it can't vs TTar.
252+ Atk Tough Claws Mega Metagross Bullet Punch vs. 0 HP / 4 Def Krookodile: 310-366 (93.6 - 110.5%) -- 62.5% chance to OHKO
Ur either in on a 1v1, in which case clear body, or rking, in which case chip means hammer arm KOes