Bubble clones are clones of playable characters that appear in the Bowser's Tower mode of Mario Party: Island Tour. They were created from "evil" bubbles when Bowser, jealous of not being invited to the Party Islands, created the tower to have his "own fun". The bubble clones can take the form of any playable character in the game (i.e. Mario, Luigi, Peach, Daisy, Yoshi, Toad, Wario, Waluigi, Boo, or Bowser Jr.), and up to three can face the player on a single floor. When encountered, they challenge the player to a minigame (the player is given two choices of what minigame they wish to play), and they must all be defeated in order for the player to move on to the next floor of the tower. Bubble clones are not encountered on floors where boss characters are, and the character that is cloned changes after the same cloned character is defeated three times (i.e. the first cloned character will appear on floors 1-3, the second on floors 4, 6, and 7, and so on).
Bubble clones can also be powered up (increased in difficulty) through Bowser's roulette. In the event that a Mini Star roulette block appears every-so-often or after three or more Game Overs in a row, Green Toad will hit it, with the number of Mini Stars displayed resulting in that number of bubble clones disappearing from that floor (if Green Toad hits the block so it shows three Mini Stars, then all of the clones will disappear, allowing the player to move on to the next floor without playing a minigame). At the top of the tower, many bubble clones of Mario appear, attempting to stop the player from destroying the machine making the bubbles, but are jumped upon and disappear. Bubble clones do not have voice clips, and their animations are identical to the character cloned.
Bubble clones also appear in the game's StreetPass Minigames mode, where the opponent in the minigame is represented by a bubble clone of the character the tagged person chose to use in the mode.