From the Super Mario Wiki
The Dark Pigarithm is a pitch black enemy from Super Paper Mario that can be found in the Flopside Pit of 100 Trials. Its name is derived from pig, referring to its pig-like appearance, and logarithm. The dark moniker comes from its shady appearance. The Dark Pigarithm is made up of three black piggy-banks connected to one another. Each time it is attacked, one of the piggy-banks is removed, making it smaller and faster. When the last one is destroyed, the player earns a large amount of coins. Surprisingly, despite being the strongest type of Pigarithms, these beasts do not award the players any points upon defeating them.
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