U-mos Jump to Oblivion

It is possible to Space Jump on top of U-mos in the Great Temple. If you are not careful when jumping around while standing on him, it is possible you can be forced into a "secret world". This is the term given for clipping/moving outside of the game map and is used for some advanced sequence breaking.

But, as of yet there is no known way to get back into the "normal world" from this area. And since it is very easy to do, it is worth mentioning that you should only experiment with this with the utmost caution as it is highly possible you will end up forced to restart from your last save.