1st appearance of Starr the Slayer, a Conan the Barbarian prototype introduced to test market interest in a sword and sorcery property

First cover collaboration of artists Marie Severin and Bill Everett who signed their artwork as "7EV" a combination of their last names

Prototype of the Watcher, first and only appearance of a pilot disguised as an alien named Zarkorr

Prototype of Hellboy

Print run: 2,000 estimated copies

Hellboy shares the cover with a character named Nathan Never, an Italian comic book character

Prototype of Iron Man, a character named Metallo who is an escaped convict in a radiation prevention suit

Prototype of Magneto

Prototype of Doctor Octopus, created by Stan Lee and Steve Ditko, published fifteen months before The Amazing Spider-Man #3, the first appearance of Doctor Octopus

Character does not take human form in story

Prototype of Doctor Strange

Prototype of Dr. Doom, specifically the design of his faceplate as seen in nearly identical detail to the Monster in the Iron Mask

Prototype of Thor, created by Jack Kirby prior to the character's introduction in Marvel Comics, Journey Into Mystery #83

Prototype of the Fantastic Four

Written and illustrated by Jack Kirby who co-created the Fantastic Four with Stan Lee three years later

In this story, one of the characters returns from space with four distinct abilities: fire projection, ice projection, size manipulation, invisibility

Prototype of Wolverine

Published 1.5 years prior to Wolverine's first appearance, a comic fan submitted an original character concept. The character was named The Wolverine with regenerative abilities, a metal exoskeleton and was the product of experimentation

The fan was not credited or compensated and there is some question as to whether the Wolverine that we know was inspired by the fan concept character

1st appearance of Dr. Mystic, a Superman prototype

Prototype of Bruce Wayne

Prototype illustration a creature with the name Hell Boy engraved on his belt

Great Salt Lake Comic Con pamphlet from 1991

Prototype of Sgt. Rock

1st appearance of Mr. Freeze, a prototype of the Batman villain with an almost identical weapon

Blackhawk #117 preceded Batman #121 by nearly two years

1st appearance of the Living Hulk, a prototype of the Incredible Hulk who was later reintroduced as Xemnu the Titan, an enemy of the Hulk

Prototype of Peter Parker's aunt and uncle, also named Aunt May and Uncle Ben

Cross-promotion text teaser for The Incredible Hulk #1, released one week later

Prototype of the Black Panther, the suit design is similar although worn by a white villain named Dr. Elixir who used the code name, The Panther

Published ten months prior to the Black Panther’s introduction in Fantastic Four #52 this issue was also written by Stan Lee

Story reprinted in Two Gun Kid #119, but The Panther prototype character was recolored red

Prototype of Captain Britain in a British fanzine

Cover appearance of 'an unknown British superhero' according to interior notes

Preceded the first appearance of Captain Britain in Captain Britain #1 (October 1976)

1st appearance of Butterfly, the first super-powered black female in comic books

1st appearance of Brice Reese, a vigilante with a customized motorcycle that included a flamethrower

Prototype of Ghost Rider, also created by Gary Friedrich

Prototype of Doctor Strange, the sorcerer Sazzik