As far as I understand the mechanic to work, the only one of these sets that benefits from the pre-Desolate Land ability is Levitate, which avoids Spikes/Toxic Spikes/Sticky Web on the first switch. In all other cases, Primal Reversion occurs before the ability makes a difference, or in the case of Sand Stream, its immediately overwritten. Speed Boost, for instance, occurs at the end of the turn. The sets themselves are fine, but they have nothing to do with the recent discovery.Primal Groudon has been unleashed!
Groudon @ Red Orb
Ability: Speed Boost
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Swords Dance
- Flare Blitz
- Earthquake
- Protect
Groudon @ Red Orb
Ability: Sturdy
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Shell Smash
- Earthquake
- Knock Off
- Aqua Jet
Groudon @ Red Orb
Ability: Regenerator
EVs: 248 HP / 112 Atk / 148 Def
Adamant Nature
- Sacred Fire
- Earthquake
- Roost
- Filler
Groudon @ Red Orb
Ability: Sheer Force
EVs: 248 HP / 252 Atk / 8 Spe
Adamant Nature
- Flare Blitz
- Earthquake
- Rock Slide
- U-turn
Groudon @ Red Orb
Ability: Adaptability
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Agility
- Earthquake
- Blaze Kick
- Extreme Speed
Groudon @ Red Orb
Ability: Multiscale
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Dragon Dance
- Earthquake
- Fire Punch
- Extreme Speed
Groudon @ Red Orb
Ability: Tough Claws
EVs: 252 Atk / 4 SpD / 252 Spe
Adamant Nature
- Dragon Dance
- Flare Blitz
- Earthquake
- Roost
Groudon @ Red Orb
Ability: Levitate
EVs: 248 HP / 8 Atk / 252 Def
Impish Nature
- Earthquake
- Fire Punch
- Roost
- Defog
Groudon @ Red Orb
Ability: Sand Stream
EVs: 248 HP / 252 Atk / 8 SpD
Adamant Nature
- Earthquake
- Stealth Rock
- Fire Punch
- Dragon Tail
There are quite literally 30+ viable sets. This doesn't even mention the many possible special sets that could actually be the hidden gems of this massive change. This fails to mention Kyogre, who's primal form gains just as much.
EDIT: Also Desolate Land Aqua Jet lol