Beware of Bouldergeist

Beware of Bouldergeist is the third level of Ghostly Galaxy in Super Mario Galaxy. In this level, Mario faces off a large rocky ghost boss called Bouldergeist.

Layout
A member of the Toad Brigade informs Mario that the monster that kidnapped Luigi in Luigi and the Haunted Mansion lives here. Mario first starts out on the Boo Mansion Gate Planet and makes his way to the Haunted Mansion. In the Haunted Mansion, Bomb Boos spawn instead of regular Boos, where Mario can use them to blow up Bowser statues where he can then access a Launch Star in the fireplace. The Launch Star takes Mario to the Phantom Tower Planets, where he needs to use Sling Pods to access a Sling Star that takes him to the second Phantom Tower Planet. In the second Phantom Tower Planet, there are two Bomb Boos, and Mario needs to collect blue Star Chips to form Pull Stars that lead Mario to another Launch Star. The Launch Star then takes Mario to the Phantom Hole Planet, where Mario needs to use a bouncy ball in one of the Hollowed-out Planets to then access the Launch Star that takes Mario to the Bouldergeist Battle Planet.

Mario has to find his way to a circular stone platform where he meets Bouldergeist, a ghost with the ability to control stone. Mario must dodge the rocks it launches, along with its hands in the second round, while grabbing the Bomb Boos and hitting its body. Mario must defeat Bouldergeist by using Bomb Boos to hit its main body three times, twice (a total of six times). Doing so causes Bouldergeist to explode, leaving behind a Power Star.

Super Mario Galaxy Trading Card description
''The battle against Bouldergeist is a two part, rock-versus-Mario smackdown. This stone specter can be defeated by throwing Bomb Boos at it three times. In part two, Bouldergeist reveals its giant rocky fists and tries to smash Mario. Continue to toss Bomb Boos to help lead Mario to triumph over this nemesis.''