Eodon

Eodon is a jungle-like, enclosed valley, where dinosaurs live beside humans. It is visited by the Avatar in Savage Empire.

It turns out that this strange mixture of worlds was created by a huge corrupted moonstone. The valley of Eodon is actually on Earth, but the moonstone has made it inaccessible and unmappable. Dr. Rafkin first puts forth this hypothesis, and it's later confirmed by a Xorinite Wisp. Only the Orb of the Moons allows travel into the valley.

The tribes of the valley of Eodon have been magically drawn from varying periods and locations in history, such as the aboriginal nations of Mesoamerica and tropical Africa.

The valley threatened to be destroyed by the corrupted moonstone, but thankfully the Avatar was able to prevent this desaster.