The Idolmaster Must Songs is a rhythm game. Though a title of The Idolmaster series, its game system is drawn from Taiko no Tatsujin. Must Songs was released in two versions, each featuring different music: Aka-ban and Ao-ban. Aka-ban features earlier music in the original The Idolmaster series, and Ao-ban features music from the 2nd Vision games; both versions contain 40 songs.
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