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Not currently, because neither of my 2 Platinum have shiny HP Rock or Fire spreads. Also, any shiny Shaymin I eventually did would have to come from an injected wondercard
Understood. Hmm. Do you still have save states from catching the ones already on your thread? Does the "rebattle code" work in such a way that you could still catch a non-shiny HP Rock Shaymin with that legit Oak's Letter?