Ukiki
Ukikis, sometimes called Ukkikis (with two Ks), are monkeys that first appeared in Super Mario 64. There is only one Ukiki seen in that game, who lives on Tall Tall Mountain. He 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. However Ukiki now runs away from Mario.
In the second mission of Tall Tall Mountain, Mario has to catch him, and he will jump on a cage with a star for him.
Ukikis also appear in Mario Party 4, in which they toss a banana. This banana, 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 really rare gold ones. They were also a capsule that would when activated would use a characters capsules.
In Mario Party 6 Ukiki appeared in Castaway Bay hosting a special coin collecting mini game.
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.
Ukikis also appear in other Mario titles, like Mario Power Tennis, where they appear in the background of a court, and in Mario Party 7, where they clean Peach's Cruiser.
An Ukiki named Akiki (who happens to be the niece of an individual Ukiki named "Ukiki") appears in Mario Party Advance.
Characteristics
Ukikis are capable of Basic Language, like most animals in the Mario universe.
