Ads keep the MarioWiki independent and free :)
MIPS, also known as the Yellow Rabbit, is a rabbit found in the basement of Peach's Castle when the player acquires fifteen Power Stars during the events of Super Mario 64. When Mario approaches MIPS, he runs away. After Mario catches MIPS, the rabbit gives him a Power Star. MIPS appears in the basement a second time after Mario has collected fifty Power Stars. Mario can catch MIPS again and will get another Power Star from him. After getting the last Power Star, MIPS will not reappear for the rest of the game.
In the remake Super Mario 64 DS, MIPS does not make a reappearance; instead being replaced by the rabbits scattered throughout the castle for each character to find. They're modeled after MIPS, but they do not give up Power Stars. Instead, they give up keys to unlock minigames in the Rec Room. Two of Mario's, one of Wario's, and one of Yoshi's rabbits can be found in the same location MIPS was in the original game.
Along with Mario, MIPS was the first character created for Super Mario 64. MIPS was used extensively in early Nintendo 64 test simulations and ultimately made it into the final game because the development team liked him so much.
MIPS also makes a cameo appearance in Mario Party 3 in Woody Woods, where several can be seen gathering near the item shop. MIPS appears in three colors: orange, yellow, and pink, which are colors matching the rabbits that replace MIPS in Super Mario 64 DS (the only absent color is green). The rabbits in Super Mario 64 DS are also internally named "MIP" with their key known as a "MIP Key", suggesting a connection.
Names in other languages