>>30203898Naive if you want to go with an all-out attacker (hjk/uturn/ice beam/filler), Rash or Naughty if you want to run Choice Scarf and get Atk and SpA boosts with each KO.
Really the only three possible natures. Avoid -Def natures since there's a chance it could live some resisted priority. It also lets you fuck with Genesect by not letting it hit your switchin with a +1 U-Turn.