Mario will venture through this level not only to search for power stars, but to also find his lost brother Luigi. Once he does, the green-clad hero will give Mario a Star, and the two will head back to the Comet Observatory. Mario will also come into possession of, for the first time, the Boo suit, which will ultimately turn him into a Boo. It is one of the few galaxies which has Boo mushrooms.
Luigi and the Haunted Mansion: Mario must navigate his way through the Galaxy's haunted mansion to find Luigi after the latter loses his way in the mansion.
A Very Spooky Sprint: Mario and the Spooky Speedster race for the Power Star at the end of a spooky racetrack.
Beware of Bouldergeist: Mario makes his way to the gravestone area where Bouldergeist makes his lair.
Bouldergeist's Daredevil Run: Mario and Bouldergeist square off again, but there's a catch: Mario must not take damage!
Purple Coins in the Bone Pen: Mario hunts for purple coins in the Bone Pen near the raceway.
Matter Splatter Mansion: Mario explores a mansion whose matter can only be touched via Matter Splatter Bubbles!