Sun-Eater
Sun-Eater
A powerful amorphous cloud-like entity that can consume entire star systems and even galaxies of stars. Wandering through space in the 30th century, it is historically responsible for the extinction of many suns -- and then, it sets its sights on the Milky Way and the earth's sun. The Legion of Super-Heroes sets out to confront the menace, but because many members are off on another mission, the Legion is forced to call on the help of the super-criminal organization known as the Fatal Five. (Adv No. 352, Jan 1967: "The Fatal Five!")
After a failed attempt to divide the Sun-Eater into smaller pieces by the villains and heroes (because the Sun-Eater has consumed many red suns, even Superboy is weakened by it), the entity is finally destroyed by a bomb made of Absorbium -- but at the cost of Ferro Lad's life. (Adv. No 353, Feb 1967: "The Doomed Legionaire!")
Apparently, a Sun-Eater is a weapon created by a powerful race of beings known as Controllers. (as revealed in Adv No. 357, Jun 1967: "The Ghost of Ferro Lad!")
