Moneybags

Moneybags (originally spelled Money Bags) are enemies that appear in Super Mario 64 and New Super Mario Bros. They are live money purses with their zippers undone and have eyes and feet. Subsequent games in the Mario franchise replace Moneybags with Coin Coffers, beginning with Super Mario 3D Land.

Super Mario 64 / Super Mario 64 DS
In Super Mario 64, two Money Bags appear in Snowman's Land. At first, they take the form of a regular, usually noticeably misplaced, coin, but when Mario gets near one, it transforms into a purse-shaped creature that hops around. After four hops, it somehow flattens up and then walks on the ground for a few seconds. Defeating one earns the player five coins. Money Bags are also featured in the Super Mario 64 DS remake and in the minigames Coincentration and Intense Coincentration.

New Super Mario Bros.
In New Super Mario Bros., Moneybags are found only in World 5-2 and World 6-3. In order to defeat one, the player must hit it with six fireballs, stomp it three times, or use either a Mega Mushroom or a Koopa Shell. For the first two ways, it gives one coin for each hit, and a 1-Up Mushroom upon the last, at which point it is defeated. Moneybags usually appear in areas with several pits, making it harder to chase the creatures by these means. The minigame Coincentration also appears in this game with more 3D-rendered graphics.