The Anunnaki are a race of creatures living in another dimension.

The Anunnaki – Library of Rickandria

Every few thousand years, during an event called Nibiru, the barrier between their world and Earth grows weak, allowing the Anunnaki to visit Earth.

Sumer & the Anunnaki – Library of Rickandria

Some of them are good and tend to help humans, while others are evil.

It was revealed that the sarcophagus buried beneath Crystal Cove contains the evilest of Anunnaki.

Anu, Enki & Enlil – Library of Rickandria

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
the Aztec’s Quetzalcoatl

among others.

Egypt: Land of Kemet – Library of Rickandria

It is revealed that the animals which can talk are descendants of the Anunnaki.

Scooby Doo is one of them.

Those who’re descendants have a longer lifespan than normal animals and have more intelligence like that of humans.

If an Anunnaki were to be destroyed, it’s presence would be retroactively erased from history with only the other Anunnaki and those close to them being the ones who remember the destroyed ones.

Hosts

Nova
Professor Pericles‘s ancestors
Scooby-Doo‘s ancestors

History

Scooby-Doo! Mystery Incorporated

Scooby-Doo! Mystery Incorporated (Intro) [HD]

Season two

An Anunnaki possessed Nova while she was in a coma and spoke to Scooby-Doo in his dreams.

Anunnaki: A Different Vision of Who They Are – Library of Rickandria

She tells him about the time of Nibiru and how their race helped humanity over the years.

Sumerian Anunnaki & the Origin of Mankind – Library of Rickandria

But she warns him of the Evil Entity that’s sealed below Crystal Cove and urges Scooby to destroy it and its curse. (Stand and Deliver)

Nova reveals on how the Entity manipulated a group of four humans and an animal to set him free and instructs them to find the Heart of the Jaguar to destroy the Entity. (Nightmare in Red)

When the Entity was freed, he opened a portal from the sarcophagus and many Anunnaki minions came forth and rounded up many townspeople for their master to feast upon.

A Different Story About the Anunnaki – Library of Rickandria

When Scooby destroyed the sarcophagus, all the minions and the Entity itself was sucked into the void and destroyed.

When the new timeline was created, Nova (still possessed) thanked Scooby saying he’s the bravest dog of all as he and his friends left home. (Come Undone)