Muk @ Life Orb
Trait: Sticky Hold
EVs: 252 HP / 4 Def / 252 SAtk
Modest Nature
- Acid Spray
- Sludge Wave
- Focus Blast
- Fire Blast / Giga Drain
I know what you're thinking, Muk has 65 base SAtk, what the hell is wrong with you?!? Well my friends, that's what good ol' Acid Spray is for. I ran some calcs on the Top 10 used Pokes in NU via the June Usage thread, and after a -2 drop in SDef and some SR support, here's what I uncovered:
252- SpA Life Orb Muk Giga Drain vs. -2 172 HP / 0 SpD Golurk: 294-348 (81.21 - 96.13%) -- 18.75% chance to OHKO after Stealth Rock
252- SpA Life Orb Muk Sludge Wave vs. -2 0 HP / 0 SpD Sawk: 294-347 (101.03 - 119.24%) -- guaranteed OHKO
252- SpA Life Orb Muk Giga Drain vs. -2 252 HP / 4 SpD Alomomola: 458-541 (85.76 - 101.31%) -- 87.5% chance to OHKO after Stealth Rock
252- SpA Life Orb Muk Focus Blast vs. -2 252 HP / 4 SpD Armaldo: 235-277 (66.38 - 78.24%) -- 25% chance to OHKO after Stealth Rock
252- SpA Life Orb Muk Sludge Wave vs. -2 252 HP / 252+ SpD Gardevoir: 153-181 (45 - 53.23%) -- 90.63% chance to 2HKO after Stealth Rock
252- SpA Life Orb Muk Focus Blast vs. -2 0 HP / 220 SpD Skuntank: 217-256 (62.53 - 73.77%) -- guaranteed 2HKO after Stealth Rock
252- SpA Life Orb Muk Sludge Wave vs. -2 252 HP / 252+ SpD Eelektross: 192-227 (51.33 - 60.69%) -- guaranteed 2HKO after Stealth Rock
252- SpA Life Orb Muk Sludge Wave vs. -2 252 HP / 104 SpD Ludicolo: 416-494 (114.28 - 135.71%) -- guaranteed OHKO
252- SpA Life Orb Muk Sludge Wave vs. -2 252 HP / 192+ SpD Braviary: 214-253 (52.97 - 62.62%) -- guaranteed 2HKO after Stealth Rock
252- SpA Life Orb Muk Fire Blast vs. -2 4 HP / 0 SpD Haunter: 316-372 (136.2 - 160.34%) -- guaranteed OHKO
As you can see, after Muk gets off an Acid Spray, you can OHKO or 2HKO a lot of Pokes off of Muk's 65 base SAtk. This set would work best in a Trick Room team so Muk didn't have to worry about forcing a switch. To discuss the moves a little, Acid Spray is the biggest move of this set to lower SDef 2 stages. Sludge Wave instead of Sludge Bomb to give a little extra boost in dmg, Focus Blast to cover Steel Types that are immune to Poison, and the last move spot is optional between Fire Blast or Giga Drain (Thunder technically is an option too). Fire Blast hits Ice/Steel super effective and gives coverage against Ghost, where Giga Drain hits the Ground/Water types this set could have issues with.
EDIT: Switched Poison Touch to Sticky Hold. Thanks for the tip Shuckleking