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In Dance Dance Revolution: Mario Mix, as the name implies, the item resembles a large heart in container. It can be bought at any shop run by a Lakitu in the Story Mode of the game. Mario or Luigi can purchase one for 170 coins. Up to three Big Hearts can be carried at a time. If Mario or Luigi had one in their possession and used it before a dance, the dance meter would completely fill up once it was empty. Even if the Big Heart wasn't necessary, it would still be gone from the item inventory. If they didn't use it, they would keep the Big Heart in their possession.