Bowser in the Sky

Bowser in the Sky is the final Bowser level in Super Mario 64 and the last one overall, in which Mario travels through platforms in the sky until he reaches a Warp Pipe leading to a final fight against Bowser to save Princess Peach and the Toads in Princess Peach's Castle. The stage also contains enemies such as Chuckyas and Goombas.

Bowser in the Sky is one of the hardest levels in the game, and Mario will need 70 Power Stars (80 in Super Mario 64 DS) to reach the top of the endless stairs, or the staircase will repeat itself. There is, however, a glitch that can be used to get up the stairs without enough Power Stars by making Mario do a Backwards Long Jump (only found in the N64 and Virtual Console version).

Bowser in the Sky is one of only three levels in Super Mario 64 DS that only one certain character can access, as Bowser will only allow Mario to enter this level. The others are Chief Chilly Challenge for Luigi, and The Secret Under the Moat for Wario.

Battle
The battle against Bowser is pretty similar to the last few fights, but there are many changes. Unlike the previous battles when the player had four mines (eight in the remake), this battle has five. Bowser is rainbow colored in this battle. This form is referred as Ultimate Koopa and does not appear in the DS remake; in that, Bowser is normal. He has new attacks. When Bowser slams the ground, shock waves will appear, and they'll damage Mario if he touches them. He retains the fireballs from the previous battle, but can also breathe a stream of fire into the air, which will fall back down a several fireballs. The last difference is that Bowser has to take damage from three mines before admitting defeat. On a side note, when Bowser takes damage from two mines, he'll shake the battlefield, causing it to form a star-like shape; this makes the third throw require much more power and timing than the first two. Additionally, each time Bowser is damaged, it becomes easier for Mario to grab Bowser's tail without having to bait him into performing the charge attack. After the third hit, Bowser will give Mario the Giant Star. When he touches it, wings will form, allowing him to fly and land in the castle grounds, where Peach and the two Toads (Luigi, Wario, and Yoshi in the DS version) are waiting for him. Mario will release Peach from above the door entrance, who bakes a cake for her heroes, and then the credits roll.

Star 1
As with the previous Bowser levels, a Power Star can be obtained by collecting the eight Red Coins found throughout the level. The Power Star will then appear behind the Warp Pipe that leads to Bowser.

Star 2 (DS only)
Below the first set of platforms that rotate much like a Ferris wheel is a large stone platform. At one end is a Star Switch. Upon pressing it, the player must backtrack a fair bit in order to collect the Power Star.

Secrets

 * The statues before the pipe at the end of the level show a depiction of Mario jumping over a Fireball near Bowser, in the old Super Mario Bros. style.
 * Like the other Bowser stage Stars, the secret Stars in this level are shown under the "Castle Secret Star" count.
 * Upon his defeat, Bowser's message to the player will differ depending on whether or not all the game's Power Stars have been collected:

Trivia

 * This course contains the 1 Whomp that isn't in Whomp's Fortress.
 * Even though seven Goombas are seen in this level, there is actually an eighth Goomba, but its spawn point is off the edge of the platform. This results in the Goomba appearing at the very bottom of the level for a single frame and then disappearing. This makes the coin inside of said Goomba impossible to collect.