Since I'm far too lazy to figure out anything (and Meganium is taken), I'll go with Bronzor.
Bronzor @ Eviolite
252 HP / 200 Def / 56 SpD
-Hidden Power Ice
Torterra doesn't threaten Bronzor very much at all (has a chance at 4HKO; does hit harder when in Overgrow but it'll kill itself before you due to LO recoil and recoil) and Altaria's Draco Meteor is a 4HKO. Hidden Power Ice doesn't hit very hard, but does OHKO Altaria once fully boosted (meaning it can't stall out Bronzor with Rest).
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