Red Lantern

Origin
The Red Lantern Corps was formed by Atrocitus, because of the rage he felt over being imprisoned and because due justice was not brought to the Guardians of the Universe, whose Manhunters had slaughtered almost the entirety of his Space Sector. Given that a Red Lanterns's rage is centrally felt over loss, he likely feels rage specifically over the loss of his sector, or the billions of years of his life lost because of his imprisonment.