Dark World 4.0

Description
Yes, another Dark World. This time, we're back to Super Mario 64. To do this one, go through one of the doors leading to the basement. Go part of the way down the stairs then get on the side. Either side. Jump, and you may or may not go through the ceiling. This may take a few tries. If it works, boom. Dark World. Although this isn't a great one, as you can get out by just walking out, if you do the Backwards Long Jump Trick against the solid side, you will go through, and will fly through the wall and into a painting.

Why it works
It's another seam.

Credit
Found on a glitch video.