No one mentioned Registeel?
I have one with 370 Defense an 402 Special Defense. He shrugs off Earthquakes and Flamethrowers like nobody's business, then fucks them up with Toxic and Seismic Toss (100 damage every turn, motherfuckers).
Plus he has Rest and Sleep Talk, so if someone does try to take that motherfucker down, he can just rebound and fuck your shit up even while he's asleep.
Here's the best fucking team ever:
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