Hariyama

Hariyama is the premier Knock Off user of ADV OU, with its Fighting typing making it a more potent offensive threat than other Knock Off users such as Armaldo and Sableye. Knock Off is Hariyama's biggest selling point because it's a way to punish Pokemon that use Leftovers to either negate sand damage or actively recover in sand depending on their typing. Knock Off can also nullify a Choice Band or boosting Berry from powerful sweepers, drastically reducing their offensive potential. Hariyama's Fighting typing also allows it to fit defensively on teams as a secondary Rock-type check. Hariyama often runs an offensively leaning set that can threaten immediate damage thanks to its high Attack stat and the powerful coverage provided by Focus Punch, Rock Slide, and Hidden Power Bug. It can also run a defensive set mainly focused on removing foes' Leftovers with Knock Off. Hariyama's versatility can make it difficult to switch into due to the threat of Knock Off from the defensive set or a powerful Focus Punch from the offensive set. Additionally, Hariyama has access to two great abilities: Guts lets it absorb status from the likes of Blissey, Gengar, and Porygon2, and Thick Fat allows it to tank special and mixed attackers that rely on Fire- and Ice-type coverage. Stat-wise, Hariyama is the bulkiest Fighting-type in ADV due to its very high base HP stat that allows it to take little damage when switching into Seismic Toss from Blissey. Due to its good bulk and not being 4x weak to Aerial Ace like fellow Fighting-types Breloom and Heracross, Hariyama is not terribly afraid of being trapped by Dugtrio. Hariyama's base 50 Speed stat means it’s the slowest of all fully evolved Fighting-types, so it can't sweep without extreme paralysis support. Hariyama's low Defense and Special Defense stats mean it has a difficult time choosing between putting EVs in both areas or pumping out its Attack stat.