NOO

The Noo is a consciousness that developed just after the Big Bang during Plank Time and encompassed all the universe until is was sealed outside of it by the laws of physics. At the dawn of the 4th Millenium AD a scientific expedition journeyed to the Hourglass Nebula and discovered the gate of Yedar, a passage leading to the dimension where Noo was bannished. The scientists were possessed by the Noo, which enabled it to interact with our universe. Its ultimate goal is to fully return to our universe by reclaiming a part of its original body-in this case, the Earth itself. The possessed warped the planet into an alternate dimension using a Density Serial Cannon. The space pirate Harlock tricked the Noo into shooting its ship the Arcadia with the weapon, allowing him to meet it on its own ground and restore the Earth.
Noo's influence on our dimension lies in creating fear in sentient beings and thereby enslaving their wills and driving them against one another.
Source: Leiji Matsumoto, Leijiverse, Endless Odyssey