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Heatran is an excellent Pokemon in ORAS Ubers as, with a Choice Scarf equipped, it can switch into +0 Mixed Rock Polish Primal Groudon's Fire Blast and proceed to hit it hard with Earth Power.
Goth lives +2 moonblast from xerneas so i wanna let u know that it's worth lowering the spe IVs just enough so that Goth can get off a psyshock after para'ing standard geoxern.