Dugtrio (M) @ Choice Band / Choice Scarf
Trait: Arena Trap
EVs: 4 HP / 252 Atk / 252 Spd
Adamant Nature (+Atk, -SAtk)
-Aerial Ace / Sucker Punch
This Pokemon traps the foe and then unleashes fury upon them. EQ for Tyranitar, Ninetales, and Politoed (not SE).
Stone Edge for Abomasnow & Ninetales.
Night Slash for Neutral. Hell, use it against Trick Room using Psychic and Ghost types.
Mewtwo @ Choice Specs
EVs: 252 SAtk / 4 SDef / 252 Spd
Modest Nature (+SAtk, -Atk)
- Grass Knot
- Aura Sphere
Grass Knot will OHKO Groudon and Kyogre (when I did the calculations, they both were 252 HP / 252 SpDef with Leftovers). Thunder and Solarbeam can OHKO as well, I just saved myself a moveslot, so Psystrike for Blissey & Co.
Flamethrower for Abomasnow. Aura Sphere will 2KHO Tyranitar.