National Dex AG
I bet none of you saw this coming because you're all so obsessed with Geomancy.
Xerneas @ Leftovers
Ability: Fairy Aura
EVs: 252 HP / 252 Def / 4 SpD
Bold Nature
- Moonblast
- Defog / Sleep Talk
- Aromatherapy
- Rest
Moonblast is STAB and is also quite powerful without investment into Special Attack. Defog removes hazards, but if you already have another Defogger like Ho-Oh or Arceus-Fairy, Sleep Talk can be used instead in conjunction with Rest. Aromatherapy heals your teammates' status condition and, if called by Sleep Talk, Xerneas's own Rest sleep, which makes it a good partner to defensive Pokemon lacking reliable recovery, such as Rest Primal Kyogre and Rest Primal Groudon. Rest is recovery.
252+ Atk Groudon-Primal Precipice Blades vs. 252 HP / 252+ Def Xerneas: 205-243 (44.9 - 53.2%) -- 0.4% chance to 2HKO after Leftovers recovery
+2 224 Atk Zygarde Thousand Arrows vs. 252 HP / 252+ Def Xerneas: 178-211 (39 - 46.2%) -- guaranteed 3HKO after Leftovers recovery
0 SpA Fairy Aura Xerneas Moonblast vs. 16 HP / 0 SpD Zygarde: 356-422 (98.6 - 116.8%) -- 93.8% chance to OHKO
252 Atk Life Orb Marshadow Poltergeist (110 BP) vs. 252 HP / 252+ Def Xerneas: 169-200 (37 - 43.8%) -- 99.8% chance to 3HKO after Leftovers recovery
0 SpA Fairy Aura Xerneas Moonblast vs. 0 HP / 0 SpD Marshadow: 374-444 (116.5 - 138.3%) -- guaranteed OHKO