Clean Mouse is a skill in the Wind Master skill tree. For each skill point allocated in this skill, a bubble will spawn at the place of a mouse's death. The bubble will appear to go from the bottom of the map and progressively float toward the top of the map. The bubble's behavior is identical to the balloon's; it travels at the same speed and pops when more than two mice stand on top of it.
Bubbles encourage rushing as mice can push the bubble to reach the cheese without the shaman. Bubbles can also be disruptive to builds as they push the shaman's build upwards
Bubbles appear quite often in the Transformice cartoon series.