Bowser in the Sky

Bowser in the Sky is the final Bowser level in Mario 64. It is accessed in the third floor, and contains the final boss fight against Bowser.

The Impossible Goomba
At one point in the stage, there is a Goomba triplet object. However, there is no space for the third Goomba, and it spawns on the death barrier.

Fwoosh
In more difficult copies, Fwooshes appear throughout the stage and attempt to blow the player off the platform. This makes the level notably more challenging, as there is no way to defeat them.