Latios-Mega (M) @ Soul Dew  
Ability: Protean  
EVs: 252 SpA / 4 SpD / 252 Spe  
Modest Nature  
IVs: 0 Atk  
- Grass Knot  
- Freeze-Dry  
- Aura Sphere  
- Flash Cannon

Groudon-Primal @ Choice Scarf  
Ability: Shadow Tag  
EVs: 252 Atk / 4 Def / 252 Spe  
Jolly Nature  
- V-create  
- Thousand Arrows  
- Trick  
- Spikes

Rayquaza-Mega @ Choice Band  
Ability: Mold Breaker  
EVs: 252 Atk / 4 SpD / 252 Spe  
Adamant Nature  
- Dragon Ascent  
- Precipice Blades  
- Trick  
- U-turn

Xerneas @ Leftovers  
Ability: Wonder Guard  
EVs: 248 HP / 184 SpA / 76 Spe  
Modest Nature  
IVs: 0 Atk  
- Substitute  
- Baton Pass  
- Moonblast  
- Shell Smash

Scizor-Mega @ Shed Shell  
Ability: Wonder Guard  
EVs: 248 HP / 252 Def / 8 SpD  
Relaxed Nature  
IVs: 0 Atk / 0 Spe  
- Recover  
- Baton Pass  
- Whirlwind  
- Defog

Chansey (F) @ Choice Scarf  
Ability: Imposter  
EVs: 248 HP / 252 Def / 8 SpD  
Bold Nature  
IVs: 0 Atk  
- Roar  
- Sticky Web  
- Lunar Dance  
- Toxic Spikes

Protean + Primal Groudon Offense by NToTheN

Latios with protean and soul dew obliterates anything it can hit. Grass Knot always ohkos Primal Groudon and Primal Kyogre. The rest is clicking buttons, but feel free to change some moves out for things like freeze-dry or other coverage if you think it's needed! Primal Groudon is there to get rid of pesky things like Mega Scizor and just generally to trap things. V-Create Ohkos Mega Mewtwo X, so don't be shy to trap it. It also has Spikes just to chip things that switch into Mega Rayquaza, and Trick to cripple wonder guards or Giratina. Banded Rayquaza deals massive damage to everything that dares come in, and Spikes from Groudon help it take down Giratina more easily. But watch out for Will-O-Wisp and Glare! Xerneas is here to provide Substitutes for the rest of the team, and Mega Scizor provides useful utility to get rid of hazards that Ray doesn't like. It also uses whirlwind to phase out things trying to set up a substitute on it. Lastly there's Chansey, which has imposter so it can transform into the opponent's pokemon, and holds the choice scarf to it always goes first. This can lead to some interesting reverse sweeps! This team can be pretty weak to Mega Gengar however, as it has the Spooky Plate which means only it can use its ghost move, and Chansey can't. I wonder how you could fix that... ;)

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