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I prefer Absolite it can use the extra Speed plus Magic Bounce. Trust me on this it would do horrible in the meta against Rock Arceus, Lando, and what ever else there is.
I honestly think Shaymin-Sky should get more recognition in this tier. It works great with Lucaronite or Absolite. I can get replays of it doing well against skilled players (people with over 1300 points). If you want proof in a real battle then my PS name is Huntress_Of_Rooted. Challenge me to...