What issue did the Red Lantern first appear in?
Red Lantern Corps
They debuted in Green Lantern vol. 4 #25 (December 2007) and were created by Geoff Johns and Ethan Van Sciver. Some of their characteristics were inspired by 28 Days Later, which is one of Van Sciver's favorite films.[1]
Guardians of the Universe
The Guardians of the Universe are a fictional race of extraterrestrials appearing in American comic books published by DC Comics, commonly in association with Green Lantern. They first appeared in Green Lantern Vol. 2, Issue 1 (July 1960), and were created by John Broome and Gil Kane.[1] The Guardians of the Universe have been adapted to a number of films, television programs, and video games.