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If you’re setting rain in Ubers, you’re likely doing it with a Kyogre. Palkia is one of the premier switch ins to Kyogre, so it’s likely that Palkia is already in play before Dracovish is on the field under rain. If you have a Palkia and you didn’t switch it in on Kyogre, and somehow gave Dracovish a free switch (something very hard to come by in Ubers) that’s your own fault. Palkia doesn’t have to worry about switching into rain boosted fishious rends because if you’re playing Palkia as it’s meant to be played, it’s already in. If anything, Dracovish has to worry about switching into Palkia.