Drapion

The first thing you may notice about this odd-looking Pokemon is its correspondingly odd Poison/Dark typing. This typing is critical to much of Drapion's success, both as a sweeper and as a defensive utility counter. Offensively, the Dark subtype grants a great offensive STAB, which in turn complements Drapion's nice movepool. Defensively, Drapion's Dark subtype gives it useful resistances to Ghost-, Psychic-, and Dark-type attacks, while its Poison subtype neutralizes the Fighting-type coverage attacks typically used by Pokemon with those STABs and offers resistances to Grass- and Poison-type attacks. This Pokemon is not a common sight in UU, but don't let that fool you--Drapion is very good at what it does, both as a sweeper and as a defensive stronghold.