ITT: We come up with ideas for new moves, abilities and Pokémon and discuss how they could affect the meta, whether it's VGC or Smogon tiers.

I will start.

>Ability: Breakthrough
>User's critical chance increases as the user's stats decreases

Assuming the ability's user has decent enough stats that it's not crippled by them and has attacks that decreases its attack/sp.attack/both, could this ability be viable? Or would Serperior outclass it with contrary?