Anunnaki

The Anunnaki are a are a race of creatures living in another dimension. Every few thousand years, during an event called Nibiru, the barrier between their world and grow weak, allowing the Anunnaki to visit Earth. Some of them are good and tend to help humans, while others are evil. The Evil Entity is considered the most evil of the Anunnaki and was imprisoned in a crytal sarcophagus buried beneath Crystal Cove. The Anunnaki have no physical forms, so they have to inhabit various animals' bodies, thus being responsible for mythological figures as the Egyptian gods, China's Monkey King and the Aztec's Quetzalcoatl among others. It is revealed that the animals which can talk are descendants of the Anunnaki. Scooby-Doo is one of them.