Ukiki
From the Super Mario Wiki
“Ook...Oookiii (I used your capsules!)”
—Ukiki, Mario Party 5
Ukikis, also known as Ukkikis or Monkeys, first appeared in Super Mario 64, where two Ukiki inhabit Tall, Tall Mountain. One can be seen following Mario around and doing tricks. However, if Mario grabs him, he will steal Mario's hat and wear it. To get it back, Mario has to grab him again; this is made difficult by the fact that Ukiki now runs away from the plumber. In the second mission of Tall, Tall Mountain, Mario has to catch a different Ukiki on the very top of the mountain; when caught, the monkey will jump on a cage with a star for Mario, making it accessible.
In the remake Super Mario 64 DS, if any character was wearing another character's hat, the monkey would take it and the character would transform back into himself. A glitch allowed Wario to pick up Ukiki using the Metal Cap and could even carry him into the water.
Ukikis have also appeared in the Mario Party series. In Mario Party 4, they toss a banana, which, upon being slipped on, will determine a character's path around the game board. In Mario Party 5 they were revealed to also come in other colors: gray, blue, red and very rare gold ones. They had their own capsule as well: when activated, the Ukiki would use all of another character's capsules. In Mario Party 6 Ukiki appeared in Castaway Bay hosting a special coin collecting mini game. In Mario Party 7 (Where they looked like Grinders), Ukikis cameoed in the background of the Mini-game Cruise, cleaning Peach's Cruiser.
In Mario Party 8, Ukikis appeared in DK's Treetop Temple, where they would roll down the stage on barrels, taking ten coins from anyone in their path. Mechanical Ukikis appeared in the mini-game Flip the Chimp. Also in the battle mini-game Snipe for the Picking there are two Ukikis turning cranks. In Mario Party Advance, a female Ukiki named Akiki (who happens to be the niece of an individual Ukiki who is named "Ukiki") appears.
Ukikis also have a place in Mario sports titles; like Mario Power Tennis, where they appear in the background of a court. They can also be seen in the audiences of Mario Strikers Charged and the Mario Baseball series.
