Green Lantern (Tomar-Re)
Green Lantern of Sector 2813, neighboring Sector to Earth's 2814.
Tomar-Re is from the planet Xudar in the third quadrant of the Xeno Galaxy.
Early in his career, the Xuadarian Green Lantern was sent by the Guardians of the Universe to prevent the imminent destruction of Krypton (S No. 257/2, Oct 1972: "The Greatest Green Lantern of All").
Unbeknownst to Tomar-Re, the Guardians were at this time considering allowing the Green Lantern Corps to operate independently, rather than taking orders from the Guardians as they had for eons. In the pairing of Kryptonian natives Jor-El and Lara Lor-Van, the Guardians saw the genetic potential for a born leader.
The Guardians wanted Kal-El, the child of Jor-El and Lara to lead the Green Lantern Corps!
Despite his best efforts, Tomar-Re was unable to either save Krypton or its people from destruction.
Kal-El, of course, nevertheless escaped to Earth where he grew up to be the world's, and perhaps the universe's, greatest hero as first Superboy and finally as Superman.