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. 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. In Super Mario 64, Mario can gain a Power Star from Bowser in the Fire Sea by getting all eight Red Coins. In Super Mario 64 DS, a Switch Star was added, bringing the total amount of Power Stars in Bowser in the Fire Sea to two.
How to Defeat
The way to defeat Bowser is the same as in Bowser in the Dark World. However, when Mario throws him off the edge, when he touches land again, the platform will start to rock at about a 135 degree angle, then will slow down, and will go back to normal. Upon defeating Bowser, Mario will receive the key to the castle's upper floors.