The Amazon is a river in South America on Earth; the term is often used to also refer to the surrounding rainforests. It has deer, volcanoes and Magma Worms.
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One of the Amazon's tributaries, the Rio Rojo, contained a Sorium deposit that was picked up by the NASA survey satellite Prospector 3, and Professor James Hobby led an expedition to the area. However, the expedition found something even more alarming was there as well - the highly dangerous Magma Worms. NASA tried to keep this a secret but the Renegades found out, and Crasher was able to attack Hobby and draw the information from his mind. Cy-Kill then planned to use the Magma Worms against the Guardians but Leader-1, Dumper and Dozer were able to trigger a volcanic reaction that buried the creatures under so much lava it would take them 17 billion years to return to the surface. The Rumbling Jungle