Bowser in the Fire Sea

Bowser in the Fire Sea is a Bowser level in Super Mario 64 and Super Mario 64 DS. The Fire Sea is made up of concrete and mesh platforms above a huge lake of lava. Several Bullies and Goombas guard these platforms and the route to Bowser's arena. The entrance to Bowser in the Fire Sea is found in the same room of Princess Peach's Castle as the entrance to Dire, Dire Docks, which in itself requires thirty Power Stars to enter. Before obtaining the first Power Star from Dire, Dire Docks, the blue portal to the water level will be in front of the entrance to Bowser in the Fire Sea. Once the first Power Star of Dire, Dire Docks is obtained, the blue portal will move to the back of the room, allowing access to Bowser in the Fire Sea. One Power Star can be found in the Nintendo 64 version of the game, while two can be found in the Nintendo DS remake.

The way to defeat Bowser is the same as in Bowser in the Dark World. However, the second battle is somewhat harder than the first boss battle with him, due to the fact that Bowser has new abilities. When Bowser gets thrown off the edge by Mario and touches land again or when Mario first meets him, the platform will start to tilt, then will slow down, and will go back to normal. Bowser can also warp to a different part of the platform to attack Mario. Upon defeating Bowser, Mario will receive the key to the castle's upper floors.

Star 1
As with Bowser in the Dark World, there are eight Red Coins to be collected. The Power Star will appear atop a wall shortly before the Warp Zone that leads to Bowser himself; Wall Jumping is required to reach it.

Star 2 (DS only)
Near where Star 1 will appear is a Star Switch. Upon pressing it, the Power Star will appear on the far side of a lava pool that the player must quickly backtrack across in order to reach it before it disappears.

Trivia

 * The crystals that Amps circle in Super Mario 64 and the DS remake resemble the crystals on the shoulders of SpaceGodzilla.