Flow Ball (Japanse: ノリ玉 Norikan)?) are pearl-like balls that can be obtained by getting a perfect in a rhythm game or clearing a challenge for the very first time 
Flow Orb

A Flow Ball

in Rhythm Heaven Megamix. They can be used to buy some rhythm games at the museum shop instead of rhythm coins that cannot be found in the story mode. You get 1 Flow Ball per Perfect, and several Flow Balls depending on the difficulty of a challenge. A total of 144 Flow Balls is required to unlock all games. And if you unlock all the shop games, there will be nothing left at the shop to buy with flow balls, so Saffron will exchange them for coins instead. 30 coins for each one will be exchanged.

List of purchasable games

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