You can keep a game's code as long as you want, it won't matter. I'm holding back codes for both Kirby games as well as Tales of the Abyss 3D.
Coins expire after two or three years of not being used. I need to spend 210 coins before they expire, and that 3DS game case would be perfect for that >_>
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Congrats to 2011 Rivalry Rumble Guru winner, SuperNiceDog
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