Bowser's Star Reactor

Bowser's Star Reactor is a level located in Super Mario Galaxy and the first level where Mario fights Bowser. Before Mario fights Bowser, he has to travel through a short level that resembles one of the Bowser levels from Super Mario 64 (the music is also the same from those levels).

After Mario passes, Bowser will come down at start breathing fireballs at the platforms that Mario is on. This causes the platforms to start breaking and Mairo then has to go from platform to platform before they break. After a while he reaches the stage where Bowser is on. Bowser laughs and the gravity of the planet above them pulls them up.

Mario fights Bowser on this planet and after he defeats Bowser, the king of the Koopas mentions that he is not defeated yet. Bowser then uses some sort of magic to disappear. Bowser leaves a Grand Star behind, which Mario gets.

The Fiery Stronghold
Mario starts the level flying through space past Bowser's air ship fleet and landing on a platform with a long path bending upwards and a giant green ring attached to it. Walking past two sticks of fire onto the path collecting coins on the way to come to a gap big enough to jump with a stick of fire six flames long. Walking on to find a crystal with a 1-up frozen in it and the main platform with two fire sticks, a flamethrower similar to the bubble guns found later in the game and a Thwomp. Up next is a green platform which rotates 180o to come to a platform with shifting gravity,(blue areas have gravity shifting down and purple areas have gravity shifting up)two black holes, four fire sticks side by side and another Thwomp. Onto a yellow platform to come to a grey platform with four fire sticks in a cross shape turning counterclockwise and a 1-up mushroom if you go clockwise. A Thwomp will try to squash you as you come into a "death zone" with three flamethrowers, a moving platform, and three groups of fire sticks, each deadlier than the last. And then its off to fight Bowser. On the way you will find a life mushroom frozen in crystal. His first attack is a stomp which will make a blue ring move around the planet, jump over it. Then Bowser will try to ground pound the player. The player should stand on a blue disc just before he attacks and Bowser will set his tail on fire when he ground pounds. He will run around the planet, and the Player must try and star spin to attack his tail that will send him spinning on his shell. The player should star spin at him again to give damage. He will then shoot fireballs at Mario and bowser will stomp him three more times. The player must repeat the attack by only star spining him when he is on his shell a few more times to end the battle.