Cobalion

Cobalion's niche in OU is being is a great Stealth Rock setter and Volt Switch user that is capable of dealing with Bisharp and Mega Gardevoir. Cobalion has a high Defense stat and access to attacks such as Stealth Rock and Volt Switch, allowing it to support its team and gain momentum. It's able to take hits due to its Steel / Fighting typing, which gives it eight resistances as well as an immunity to Poison-type attacks. However, Cobalion has mediocre offensive stats that make it difficult for it to dish out heavy amounts of damage and achieve KOs, so it rather easily handled by common Pokemon. Although Cobalion is only weak to Fighting-, Fire-, and Ground-type attacks, offensive moves of these types are common and thus still manage to cause massive problems for it.