Pluto Ultima

Pluto Ultima was a planned planet set to be made when Pluto 4 is made. It is planned to be made by having Pluto 4 collide with Pluto 3.

It was destroyed by the Mongolia in Chapter 3 Part 13 after flying into space from crashing onto Dr. Smart and SpongeBob SquarePants. It was later succeeded by Pluto Ultima 2.