>>36893666mewtwo and megazard are insta banned since nothing in this list can take a hit let alone check zard Y besides an opposing zard X or dragonite. if it doesnt get drought tho then it might be fine. mega gengar kinda sucks and so does mega kanga because they lose their abilities making mega zam mega bro and mega gyara much better picks. top tiers for every type
normal: tauros, lax, eevee, alola rat
grass: mega venu, eggy
poison: mega venu, mugg, gengar (holy shit did the ability and item nerf hurt weezing and nidoking)
fire: zard, moltres, arcanine
flying: zard y, moltres, zapdos, gyara, dnite
water: pretty much every water but dewgong, poli, seadra, seaking, and lapass is good
dark: all of them because zam and eggy rek house
electric:alolachu, pikachu, zapdos
psychic: zam, mew, alolachu, eggy, slowbro
ground: rhydon
ice: ninetails alola, jynx, cloyster
steel: duggy alola i guess
dragon: all of them are good
rock: golem alola maybe, aero, omanyte, rhydon
fighting: hitmon lee, champer
ghost: come on now
bug: scyther, venonat, mega pinsir (kinda sucks with no ability)
fairy: clef