Kid Icarus: Uprising - hearts = money

"In this game, like the original, hearts are money. The higher the difficulty that you play and succeed at, the more hearts you'll receive and the money you'll receive. And those hearts can, then in turn, be used to buy things or, without saying too much, offered up to Palutena." - Masahiro Sakurai

Straight from 1up's feature '20 facts from 20 games you don't already know'.
 
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