porygon2 from B rank to A+ rank (RIP cased)
seriously, duck is an amazing lord of destruction. basically it counters
literally every pkmn that isn't a fighter or has recovery. this includes: nidos, salamence, mega aero, chandelure, feraligatr, crobat, mega pert, (mega) pedo, mega scept, mega glalie, slurpuff, and much more. it can take two close combats from non cb ape which is pretty brutal already. in some games it ends up being a win condition just because offense cant kill it, and basically all the support it requires is cleric + fighting counters.