Deep Dark Galaxy
Deep Dark Galaxy is a ghost-type galaxy in Super Mario Galaxy, like the Boo's Boneyard Galaxy and the Ghostly Galaxy. However, the main planet in it has a beach with many Toads and crab-like enemies. There are also Magikoopas near it. The thing that makes it "spooky" is that there is an underwater cavern (it's rather dark, giving the Galaxy its name) filled with "ghost ships". There are very few planets aside from the big, main one. This is also the second appearance of Guppy.
Levels
The Underground Ghost Ship
Bubble Blastoff
Guppy and the Underground Lake
Boo in a Box
Ghost Ship Daredevil Run
This is a semi-difficult challenge involving good skill. Mario starts off in the scene where he lands in front of the ghost ship that is surrounded by Boos. The player will have to go on the ghost ship to fight Kamella, the ugly Magikoopa. The trick is to successfully defeat the clever witch with only one health point. Every now and then Kamella throws a green shell at Mario, which he must use to attack her. The best way to defeat Kamella is to take out the Magikoopas and then wait for her to throw a shell at Mario. Once Kamella is defeated, the player gets a Power Star.
Helpful Hint: Before boarding the ghost ship, the player also has the option to dive down under the ship, collect the ? Coin, and recieve an extra life for collecting fifty or more star bits.