World 6, also known as World 6: Bowser in Your Sights, is the sixth world in Super Mario Galaxy 2. The whole world is located in close to a large red and orange Black Hole. It is at the center of the universe. It holds seven galaxies, with the last galaxy being the final boss galaxy in the game, Bowser's Galaxy Generator. Here, Mario fights Giant Bowser for the final time. If Mario defeats Bowser, he is shown reconnecting with Peach on the Garden Planet before the final Grand Star is collected. Afterwards, Luigi is unlocked and the end credits will begin to roll.
- Melty Monster Galaxy
- Clockwork Ruins Galaxy
- Throwback Galaxy
- Battle Belt Galaxy
- Flash Black Galaxy (this galaxy is unlocked by feeding Star Bits to a Hungry Luma on the map)
- Slimy Spring Galaxy
- Bowser's Galaxy Generator
- This galaxy's music is a slowed-down version of the music that plays during the battles with Bowser in this game.