Gardevoir

Gardevoir's superb Special Attack stat in combination with its fantastic offensive typing leaves it as one of the most ferocious special attackers in the UU tier. With access to great coverage options, such as Focus Blast and Shadow Ball, it becomes quite hard to switch into for all different archetypes. Its decent Speed tier allows it to outpace the likes of Florges and unboosted Feraligatr and Speed tie with Mamoswine and Chandelure; however, against offensive teams, it can be quite lacking. With high Special Defense for an offensive Pokemon, Gardevoir is able to soak up special attacks from the likes of Suicune and Florges quite easily. Last but certainly not least, Gardevoir's access to Trace allows it to copy the foe's ability, which is extremely helpful for foes with abilities such as Regenerator, Flash Fire, Swift Swim, and Sheer Force.

Sadly, Gardevoir has terrible Defense, leaving it open to easy revenge killing from the likes of Entei, Mega Absol, Crobat, Mega Aerodactyl, and Krookodile. On top of that, it has a lot of issues breaking past certain Steel-type Pokemon depending on its coverage. For example, Doublade fears nothing except Shadow Ball, and Mega Aggron uses it as entry hazard setting fodder unless it has Focus Blast.