Probopass

Probopass is an odd-looking fellow, isn't he? Sporting an immense 145 base Defense and 150 base Special Defense, Probopass has the ability to take many hits and support his teammates with decent support moves such as Stealth Rock, Thunder Wave, and Gravity. Additionally, Probopass's Magnet Pull ability is somewhat useful, as it traps the few Steel-types in UU: Registeel, Steelix, Aggron, and Magneton. Everything looks good so far! However, upon closer inspection you'll notice that he's lacking in HP, while his typing gives him an unfortunate 4x weakness to both Ground- and Fighting-type attacks. Probopass is a flawed Pokemon, but if you give him the right support and cover his crippling weaknesses, he becomes a decent supporter and an unbreakable wall capable of checking many threatening Pokemon that reside in UU, such as Houndoom, Rotom, and some variants of Spiritomb.