Haxorus

Haxorus is one of the few viable Pokemon that have the ability Mold Breaker, allowing it to bypass abilities like Multiscale and Sturdy from common Pokemon like Dragonite and Magnezone. Additionally, its pure Dragon typing gives it only three weaknesses and one resistance, allowing it to take on a lot of Pokemon in the metagame thanks to its high Attack stat and vast movepool with high-Base Power moves like Outrage, Iron Tail, and Superpower let it break past Pokemon like Mega Venusaur, Tapu Lele, and Mega Tyranitar. However, Haxorus does suffer from mediocre HP, Special Defense, and Defense stats, which means it cannot take a Z-Move from Aegislash or live a super effective attack from Garchomp, Magearna, and Naganadel. Furthermore, Haxorus has an awkward Speed tier that allows it to outpace Tapu Lele, but not Pokemon like Mega Charizard X without having to run Choice Scarf and losing power. It is also outclassed by other Mold Breaker Pokemon like Mega Gyarados, which can check physical attackers like Landorus-T thanks to its pre-Mega Evolution ability Intimidate and can take care of Sturdy Pokemon that Haxorus can like Magnezone thanks to Earthquake while also taking care of Pokemon that Haxorus cannot take care of, like Donphan.