10 DC: Supergirl

Supergirl debuted in Action Comics #252 as a female counterpart to the superhero Superman (1959).

9 Marvel: Silver Surfer

Created by Jack Kirby, the Silver Surfer first appeared in the Marvel comic book Fantastic Four #48 (1966).  

8 DC: Captain Atom

The first appearance of Captain Atom (Nathaniel Adam) was in Space Adventures #33 (1960), which was written by Joe Gill and illustrated by co-writer Steve Ditko.

7 Marvel: Grand Master

Created by Roy Thomas and John Buscema, the Grand Master first appeared in The Avengers #69 (1969). 

6 DC: Superman Prime

Featuring a vision of a future DC Universe in the 853rd century (85,201–85,300 AD), Superman Prime was introduced in 1998 through the DC One Million crossover series. 

5 Marvel: Phoenix 

The Phoenix Force is a child of the universe and was first introduced as a Jean Grey impersonator (Phoenix) X-Men #101 (1976). 

4DC: Guardians Of The Universe

Commonly associated with Green Lantern, the Guardians of the Universe first appeared in Green Lantern vol. 2, #1 (1960). 

3 Marvel: The Twins: Infinity/ Eternity

Infinity was created by Mark Gruenwald and Greg Capullo, appearing for the first time in Quasar #24 (1991). 

2 DC: Elaine Belloc 

Elaine Belloc is the first being created by birth from an angel. Her biological father is Archangel Michael.  

 1 Marvel: One-Above-All

According to Marvel Comics legend, One-Above-All is solely responsible for the existence of all life in the Multiverse.