Rupees are the currency of Mushroom Kingdom Fusion. They come from the Legend of Zelda series, where they served the same purpose. They don't appear as much as coins do. However, they can be exchanged for very powerful items in Shops.
Rupees are acquired by defeating enemies, found either in the open or in Containers. They are stored separately from coins. The amount that can be carried is also greater than the number of coins, though the exact maximum amount that can be carried is currently undecided. They come in units of one (green), five (blue), ten (yellow), twenty (red), and fifty (purple). Collecting black Rupees, known as Rupoors, will decrease the player's amount, losing twenty rupees. There are also giant variants of Rupees, which multiplies by a hundred (e.g., one giant green rupee is worth one hundred rupees).
Enemy Currency[]
Many enemies drop rupee equivalent currency when killed, each type worth its own value in rupees. These dropped items' sprites are generally themed to their enemy's game. For example, Mega Man enemies drop bolts, Mario enemies drop Wario Land 4 coins, Zelda enemies drop rupees, etc. There are also a number of generic money drops that cover loose end enemies while cameoing obscure gaming currencies.