Arceus-Poison @ Toxic Plate
Ability: Multitype
EVs: 248 HP / 52 Def / 152 SpD / 56 Spe
Impish Nature
- Defog
- Recover
- Poison Jab
- Will-O-Wisp
Firstly, covers up the the xerneas weakness.While the team is kinda balanced and will be requiring switchin', so a defogger will play a vital role in keeping off the Stealth Rock/Spikes/Whatever.Finally, it's a decent yveltal switching (Just to scout if the yveltal has knock off, as if xern's switched in and choice scarfe is knocked, it can be a bit of trouble...)
Evs:You can either switch the defense Evs for SPD or a bit of speed creep