"Deep in the desert there sits a beautiful oasis, ruled by a monarch unlike any other in Erdas. His name is Cabaro, the Great Lion, and he reigns over a kingdom of animals, jealously guarding his golden talisman. No human has ever set foot on the Great Beast's territory. The journey to his oasis is impossible. As a team, Conor, Abeke, Meilin, and Rollan have achieved the impossible before. But now that team is broken--the friends scattered by a devastating...

A new threat -- something ancient and evil -- faces the world of Erdas and four young heroes and their spirit animals are determined to stop it as they embark on a desperate journey that takes them deep underground and to the far corners of the world.

"When the shadowwalkers were victorious in their battle against the Ant Queen, they hoped their work to save Caldera was done. But the rainforest has begun to rumble. Rumi, a scholarly tree frog who can control the wind, must bring his band of animal friends to face the greatest danger they've yet encountered--the giant volcano beneath the jungle itself. While the volcano roars, rumors of a mysterious evil blanket Caldera--the Elemental of Darkness...

"Deep in the desert there sits a beautiful oasis, ruled by a monarch unlike any other in Erdas. His name is Cabaro, the Great Lion, and he reigns over a kingdom of animals, jealously guarding his golden talisman. No human has ever set foot in the Great Beast's territory. The journey to his oasis is impossible. As a team, Conor, Abeke, Meilin, and Rollan have achieved the impossible before. But now that team is broken--the friends scattered by a devastating...