Space

Space (or Outer Space) is a continuous void of nothing. The contestants have been here at several points.

Cover
In Sweet Tooth, Needle's cake has grown to the size of a planet and floats in space (Making Earth a triple planet system), but it popped by Needle in Bridge Crossing.

The contestants are flung into space (due to budget cuts) in Gardening Hero. They return to Earth in the next episode.

Yoyle Mountain is so tall, it's summit is in space.

In Gardening Hero, Yeah, Who? I Wanna Know! and Getting Teardrop to Talk, Black Hole lives in space instead of Earth because of how big they are. However, they are crushed down to a smaller size and now live in Goiky with the other contestants.

Trivia

 * The Announcer is possibly from space
 * The laws of space apparently don't apply, as the contestants can breath and Ice Cream Cake does not explode