The Purple Coin Host is a character that made her only appearance in Super Mario Galaxy and Super Mario Galaxy 2. As her name suggests, it hosts the Purple Comet of the Battlerock Galaxy. Another Gearmo hosts Purple Coin in the Dreadnought Galaxy.
In Super Mario Galaxy's Battlerock Galaxy, Mario needs to grab 100 Purple Coins while keeping his distance from the electric wires and the cannonballs. At the end, the Purple Coin Host will tell him how well he did. If it is 100, Mario will get his Power Star. If it is less, he will lose a life.
The Purple Coin host makes her second appearance in the Tall Trunk Galaxy, where it dropped 140 Purple Coins on the Trunk Slide. She asks if Mario will go down the slide and grab at least 100 of them on his way down. That done, her brother will award Mario with a Power Star.
- In her rant when it sees that Mario gets no Purple Coins, the Purple Coin Host refers to herself in the third person, calling herself an "old iron lady", indicating that Gearmos actually are gendered separately.