Altaria

Altaria is often known as the "UU Dragon" because it's simply outclassed by Dragonite and other Dragons in OU. While it is outclassed in OU, it has a very interesting niche in the UU metagame. Being able to resist many of the most common attacks that are used in UU (Grass, Fire, Water, and Ground) as well as resisting common priority moves (Aqua Jet, Vacuum Wave, and Mach Punch), Altaria makes a great special wall and bulky Dragon Dance sweeper. Altaria's Special Defense is often high enough to even take Ice-type attacks after a Roost.

While Altaria is a great defensive Pokemon, it's often held back by its mediocre offensive stats. Draco Meteor and Outrage compensate for this to an extent; however, even with these moves Altaria has trouble dealing enough damage to sweep without Dragon Dance boosts. After a Dragon Dance, however, with perfect coverage granted in two moves, decent Speed, and a 120 Base Power STAB attack, Altaria will be able to devastate unprepared teams.