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Why is Sylveon so valuable
It must be summoned by tributing at least 2 monsters with different names
Sometimes I will take my laptop to the library in the evening and catch up on my email there
Because rare slots are split between Holo Rare, Pokemon-ex, Secret Rare, Shining, Crystal and Gold Star tiers (depending on the era), individual ultra-rare odds can run an order of magnitude lower than headline 1-in-3 holo-slot rates
Not only that, but it would be unaffected by other card effects making it near impossible to get rid of, as you couldn't even Kaiju it with the summon restriction