Since the resurgence of Hoopa-U with its new Z-Move set as well as other stuff as of recent, I've been tinkering with this rly silly double trap core with Scarf Magnezone and Alolan Muk and it performs decently well with some testing.
Magnezone @ Choice Scarf
Ability: Magnet Pull
EVs: 4 HP / 252 SpA / 252 Spe
Timid Nature
IVs: 1 Atk
- Thunderbolt
- Hidden Power [Fire]
- Flash Cannon
- Volt Switch
Muk-Alola @ Assault Vest
Ability: Poison Touch
EVs: 248 HP / 112 Atk / 148 SpD
Careful Nature
- Rock Slide
- Pursuit
- Poison Jab
- Knock Off
So the premise would be that Magnezone lets you eliminate things like SD Kart, MZor and friends out of the picture while Muk-A sponges and deals with the likes of Blacephalon, Hoopa-U and Lele as they are easily fodderized, and with Rock Slide you're able to pretty much hard stop Volcarona no questions asked. The EV spread just hits a jump point with Assault Vest in SpD while dumping the rest in Attack, and Fire Punch or Blast isn't needed since you know.
Definitely far from perfect though as ground and Heatran weakness is extremely annoying, so you might wanna patch this up with say SR Lando (possibly yache since Koko isn't smth you wanna deal with either), but the concept is definitely cool and there's probably a variety of Pokemon to abuse this with (M-Latios comes to mind as it works rly well with this, Muk-A pretty much acts as an extension to the duo that patches up some defensive issues). Muk-A can be a bit of a momentum sink but its bulk and typing just lends you a safety net vs a combination of mons known to be difficult to defensively answer especially in one slot.