Bowser in the Dark World
Bowser in the Dark World is the first Bowser level in Super Mario 64 and Super Mario 64 DS. It is a puzzle-like world with many traps and enemies. The trapdoor entrance is behind the star door in the main floor. Eight Power Stars (twelve in the DS remake) are needed to open this door.
In the corridor before entering the level, a painting which depicts Princess Peach is seen on the far wall. As the player walks closer, the painting will become a picture of Bowser and a trap door will open in the ground, sending the player into the level. The Princess Peach painting is not able to be reached, as there is an invisible wall between the player and the painting.
 Bowser in the Dark World
The first section of the level is pretty straight forward. There will be a single Metal Box or ? Block followed by a Fire Shooter. Two moving pyramid-shaped platforms join onto a tall stone platform. The blue route is safer, but is too steep for Mario to run up normally: he will have to strategically use his jumps to get up. The stone route is longer, flatter and has coins, but there is a Fire Shooter at one end of it which Mario may run in to. More moving platforms lead to the next section of the level.
Next is a wooden octagonal shaped platform which three Goombas await Mario, as well as a Yellow Exclamation Mark Block in the middle containing a 1-Up Mushroom. Connected to the platform is a wooden bridge linking to a path made out of a type of green stone. Six crystals are stuck in the path, four of which are being circled by Amps. They also resemble Item Crystals from Super Mario Galaxy; however, they cannot be broken by any attack. At the end of the path, Mario would have made a U-turn to a large stone cube, which a yellow rectangular block will continue protruding in and out of it. Another yellow Exclamation Mark Block containing three coins will hang above this. Two sets of circling platforms will lead Mario to the final section of the level before the Bowser fight.
Mario will almost instantly get ambushed by a single Goomba, which he can easily defeat. To the right are two purple tilting platforms, though behind them Mario can collect two 1-Up Mushrooms, and on the overhanging platforms he can collect another two. There will be two Goombas on a stone block after the tilting platforms, after which Mario must climb up some stone platforms to hit a ! Switch which activates a staircase which leads Mario to the Warp Pipe to Bowser.
Once Mario enters the pipe, Bowser will show up saying that Princess Toadstool isn't in the Dark World. Bowser will attack using his trademark Fire Breath which can burn Mario. He can also jump up and shake the ground if Mario is too far away. While fighting Bowser, Mario must grab him by his tail, twirl him around to build up momentum, and then throw him into one of the four mines available (In Super Mario 64 DS, there are eight mines). Upon doing so, he will admit defeat and disappear, leaving Mario with the key to the castle's basement.
 Enemies Encountered
 Star 1
Eight Red Coins can be found throughout this level, many of which are difficult to obtain due to the fact that there are many gaps and narrow bridges in the course. The locations of the Red Coins are as follows:
Upon collecting them all, the Power Star will appear near the Warp Pipe that leads to Bowser.
 Star 2 (DS)
In Super Mario 64 DS when Mario gets near the end of the level, he will find a Star Switch placed next to the Warp Pipe leading to Bowser. Mario must then continue forward and jump over high ledges to reach the Star Switch. He must then go back and repeat the steps to go back to the glass containing the Power Star throughout a limited time. If Mario doesn't make it, he will have to repeat these steps all over again.
The stage music is the same as in Bowser in the Fire Sea and Bowser in the Sky, with "Koopa's Road" being used for the course (but not while fighting Bowser). This music is re-used for the DS remake and the Bowser stages in Super Mario Galaxy and Super Mario Galaxy 2.
 Names in Other Languages