Think about it like this, in real Topps products, It's around a 1:10 chance you will pull a rainbow foil variation. That doesn't mean you are guaranteed a rainbow foil on the 10th pack. It just means for every 10 packs Topps made, one has a rainbow foil. You could get unlucky and open 20 packs and not get a rainbow foil.
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chellechris1225
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