Aron

Aron is a gimmick Pokemon that can catch people off guard if they don't have the proper resources or experience on their team to counter it. This gimmick specifically relies on Sturdy, allowing Aron to take a hit from almost any Pokemon barring ones with status moves, Mold Breaker, or multi-hit moves. With the combination of level 1, Sturdy, Shell Bell, and Endeavor, Aron is able to take a hit, use Endeavor to bring the opposing Pokemon down to 1 HP, heal back all of the damage with Shell Bell, and eventually use either Sandstorm, Metal Burst, or Toxic to finish off the foe. This lets Aron beat Pokemon that cannot deviate from attacking like Dragonite, Donphan, Mega Altaria, and Meloetta. However, an abundance of status moves including Will-O-Wisp, Sleep Powder, Taunt, and Substitute all stop Aron from completing the task at hand. Furthermore, Mold Breaker Pokemon like Haxorus and Mega Gyarados can go through Sturdy and OHKO Aron. Lastly, flinching moves are also prevalent in the metagame. Though Aron can block Fake Out if it is running Protect, moves like Iron Head and Air Slash used by Pokemon like Jirachi, Mega Mawile, Mega Charizard Y, and Togekiss make matchups with them unreliable, as one flinch can catch Aron off guard and leave it open to being KOed the next turn.