"They told me this tale. A story about a creature that was born at the beginning of sentience. A yellow entity that was made of living fear. It created terror into anything it came in contact with. Caused entire civilizations to destroy themselves out of paranoia. Their fear was eaten by this creature....
[It] threatened to consume the entire universe. It wanted to infect every living creature with fear, and fear leads to violence. Violence leads to fear. Like an endless loop of death and destruction."
-from Green Lantern: Rebirth #3 by Geoff Johns