Parallax

Parallax is the Embodiment of Fear in the Emotional Spectrum, birthed back at the dawn of time when the Life Entity entered into the universe and sheltered itself on the planet Earth.

Background
Appearing as a demonic parasite cosmic entity, Parallax traveled from world to world and caused entire civilizations to destroy themselves out of paranoia. The Guardians of the Universe later imprisoned Parallax within the Central Power Battery on Oa where Parallax lay dormant for billions of years, his presence in the Power Battery menifesting itself as a weakness for all Green Lanterns against the colour yellow.

Choosing Green Lantern (Hal Jordan) as his host to escape the Power Battery, Parallax influenced Jordan and, following his despair after the destruction of Coast City, took full possession of the Lantern and set about destroying the Green Lantern Corps and killing the Guardians of the Universe. Following Jordan's sacrifice to save the Earth, Parallax was trapped with Jordan until his resurrection whereby the entity once again attempted to take possession of the Lantern only to be captured by the Green Lantern Corps and re-imprisoned in the Central Power Battery.

Trivia

 * Parallax first appeared in Green Lantern vol. 3, #50 (March 1994)
 * Parallax is shown to be the second Embodiment of Emotion that was formed due to the Life Entity's influence.