For sure not gonna be unbanned, but just imagining this thing with Shed Tail Support...
Free my boy, Bax is better than him (EDIT: I forgot Teravolt lets you bypass Unaware)
I feel like it'll be a bit insane in practice. This thing is a top tier defensive mon in Ubers, and types that don't carry ghost and dark types won't be able to break. Even if you have a coverage move you're doing like 60% max if it's non stab, and that's not counting the fact this will be spreading burns, has reliable recovery, and ice beam coverage.
HMMMMMMMMMMMMM??? Could maybe be tried, it's strong and bulky for sure but the Speed tier and defensive typing are both horrible. Possibly too much with Trick Room I guess
252+ Atk Sneasler Night Slash vs. 148 HP / 160 Def Shadow Shield Lunala: 158-186 (34.9 - 41.1%) -- guaranteed 3HKO
252+ Atk Scizor Knock Off (97.5 BP) vs. 148 HP / 160 Def Shadow Shield Lunala: 216-256 (47.7 - 56.6%) -- 87.5% chance to 2HKO
252 SpA Choice Specs Iron Valiant Shadow Ball vs. 148 HP / 0 SpD Shadow Shield Lunala: 234-276 (51.7 - 61%) -- guaranteed 2HKO
0 Atk Great Tusk Knock Off (97.5 BP) vs. 148 HP / 160 Def Shadow Shield Lunala: 164-194 (36.2 - 42.9%) -- guaranteed 3HKO
252 Atk Choice Band Zamazenta Crunch vs. 148 HP / 160 Def Shadow Shield Lunala: 230-272 (50.8 - 60.1%) -- guaranteed 2HKO
We don't know in practice how it'll actually turn out, and what sets would be used/changed for the metagame, but I don't see how this would not be pretty unbreakable for types like ground, fighting, and flying. Flying's main toxic abuser - gliscor - gets an ohko roll from 0 spa ice beam. If it turns out to be a more offensive lunala set - like Meteor Beam/roost/ice beam/moongeist beam for example, flying doesn't have much to respond with there either. Since it is monotype, the calm mind set would probs be used for something and roll a few types.
You also forgot TRAPINCH
, monotype's hero. Able to trap and OHKO prominent threats to mono ground such as Ogerpon-Wellspring, Chien Pao, Meowscarada, Greninja (though protean makes this a maybe), Samurott-Hisui, and Hoopa U. Be prepared to type variants of the name such as Tr@pinch or Trap!nch or something along those lines, the anti-Trapinch lobbying groups (maroon) will be sure to lock down the Trapinch discussion from discord and VR.I'd imagine Suicune
also does well, though it may be more of a post Waterpon/Firepon meta (let's ban those two this time round plz). Grass will likely appreciate the return of Whimsicott
as well, helping with the dragon and dark mus though I imagine the strong Ice Mons on those types will still be incredibly difficult to get past. Reuniclus
always sees usage as a matchup mon, though Psy's structure will be questionable if Lati's don't get defog. Galvantula 
is back as a reliable sticky webber, + electric coverage for bug. Lastly, Incineroar 
may see usage on Fire as a pivot with Knock Off + Parting Shot + Taunt support, I doubt it'll have toxic though which may be a bit of a changer for it.Only other thing worth mentioning are the rumors of a Dipplin evo. I doubt it'd be a mainstay on either Grass/Dragon, but depending on stats, moves, and ability, there could be small niches it carves out for itself.
Skarm coming back will be huge for steel. In combination with 
not only is Bulky spike stack extremely viable, but Hyper offense suicide lead as well. This makes steel less of a 1 trick pony playstyle and gives it alot better match ups.
Waters staple is back, making iron hands electric less annoying, and also making rain kinds viable again with rocks+flip turn.(no momentum drain) Here's the 6 I'd probably use once it drops:
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or 
/Potential Terrak Paradox as two examples. I imagine the Terrak team would at least have better matchups if we do get that but either way I don't see how Psy can really address the dark mu, and no matter how you dice it, it's difficult to have freedom with the slots.
