Muk-Alolan @ Assault Vest
Ability: Poison Touch
EVs: 248 HP / 100 Atk / 92 Def / 64 SpD / 4 Spe
Adamant/Brave Nature
- Knock Off
- Pursuit
- Gunk Shot/Poison Jab
- Shadow Sneak/Brick Break/Fire Blast
First off, major credit to this set goes to Vengeance417. "Physical bulk prevents Latios's EQ from 2HKOing you, special bulk prevents Latios's Draco Meteor from doing half, keeping you relatively healthy and still dodging the EQ knockout (although you'll most likely die after rocks, so keep those off the field), 4 speed to creep on opposing 50s such as Tangrowth and the rest in Attack."
Knock Off and Pursuit being STAB are amazing, and with Poison Touch you have a 30% chance to poison whatever you're hitting as well, which is excellent, especially versus defensive switch-ins like Landorus-T and Garchomp. Gunk Shot/Poison Jab are your choices of Poison STAB, with Gunk Shot packing significantly more power at the cost of accuracy and PP and most importantly, lack of contact means Gunk Shot only has a 30% chance to poison as opposed to the 51% of PJab. Shadow Sneak is your only form of priority (until hopefully Sucker Punch gets released), but it's still serviceable given your naturally decent Attack stat. If you don't really want the priority, you can run Brick Break to hit things like Ferrothorn, Tyranitar, and Bisharp on the switch and do good damage to them. If you choose to run Fire Blast in the last slot, use 44 SpA EVs and a neutral SpA nature to 2HKO max SpDef Mega Scizor and standard Ferrothorn, both of which wall you and can set up on you otherwise.