Clefable

Clefable acts as an anti-metagame wall that can beat even the most formidable of setup Pokemon in 1v1. Using Psychium Z, it can opt to boost either of its defensive stats with Z-Magic Coat or Z-Reflect, allowing it to beat common threats like Mega Charizard X and Y, Mega Gyarados, Dragonite, and non-Gunk Shot Greninja. Its powerful ability Unaware allows it to tackle Pokemon that might try to set up and break through its defenses like Mega Charizard X and Landorus-T. However, despite its good defenses Clefable can still fall prey to powerful super effective attacks from the likes of Mega Metagross, Naganadel, and Genesect. Furthermore, while Unaware ignores the stat boosts of enemies, Clefable's own defenses can still be lowered, allowing Pokemon like Magnezone, Aegislash, and Nihilego to beat it. Finally, some attacks like Choice Band Victini's V-create and Porygon-Z's Breakneck Blitz can be too much for Clefable to handle, even with defensive boosts.