Endless Island Portal

The Endless Island Portal serves as the entrance to the island itself. When a visitor uses their key or totem, they are transported by a colored energy wave through a black empty expanse until they reach the island's realm and appear on or near the portal.

The portal was last seen being destroyed by the Butt Witch in the episode Together Forever.

Appearance
The portal is made out of lots of different shapes. An orange sphere, a pink arch, a red tillted V-Shape, and a shashwick-looking thing with four lime-green spheres attached to it - the second one being the biggest, and the last one being the smallest.

Trivia

 * For some reason, standing on the portal is not required to leave the island, even though visitors have been seen using it as a formal way to return home.