Gearmo
Gearmos are robot allies that appear in Super Mario Galaxy. Most Gearmos live in the Toy Time Galaxy. Gearmos can be also found in the Buoy Base Galaxy, the Battlerock Galaxy, the Dreadnought Galaxy, and Grand Finale Galaxy. A green one is also controlling the Engine Room.
Two Gearmos holding magnets attached to metal sticks are shown in the game. They are in charge of keeping the ammo depots in the Battlerock Galaxy and the Dreadnought Galaxy clean. They ask Mario to help them by throwing Bob-ombs at the garbage. It is possible that both Gearmos are the same, since both are green.
Gearmos have a large gear inside the back of their heads. If Mario jumps on the gear, it pops out, and falls back into place. Gearmos are capable of moving without the gear, suggesting that the gear has no real purpose. This may also indicate that Gearmos are living beings rather than robots.