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Idk, the thing with kyurem was that it was debatable over the edge. Compared to baxcalibur, the bullshit level was noticeably lower, it required support and the reward, while good, is still arguably lower than Gambit, Valiant, or Ghold imo. I was also one of those weirdos on the fence on it last Gen.
Raging bolt is like Kyurem with CM, booster energy, and priority + is op in multiple weather's. Gouging Fire is hard x with an item slot, as you said. I think it's fine on non-sun, but it's damage is also jacked up by the weather to unreal levels.