The Flash, stranded, contacts then-DC Comics editor Julius Schwartz,[1] who helps him construct a cosmic treadmill to return to Earth-One.

Eventually, it was stated that the writers of DC Comics of Earth Prime subconsciously base their stories on the adventures of the heroes on Earth-One and Earth-Two.

Post-Crisis on Infinite Earths in 1985, when there was no longer an Earth-Prime or greater Multiverse, Ultraa was retconned into being from the planet Almerac, homeworld of Maxima.

Superboy-Prime escaped his universe's destruction and later joined Earth-Two's Supermanand Lois Lane and Earth-Three's Alexander Luthor in traveling to another dimension.

Writer Kurt Busiek states in the introduction to the collected volume of the series that the original appearance of Superboy-Prime was the inspiration for his graphic novel.

Ultra is the only metahuman on Earth-33, fighting the encroachment of the "Gentry" (the series' lead villains) by confining their presence on "our" world to the pages of an 'entrapment comic book' built around the title character.

On some occasions, various characters of the Marvel Universe, looking for their version of God, encounter 'real world' figures such as Jack Kirby and Stan Lee.

Though not using the term "Earth Prime", Roger Zelazny's The Chronicles of Amber fantasy series features a similar concept.

Although the true "Earth Prime" of the movie would be that inhabited by Kevin Eastman and Peter Laird in the closing shot, shown putting the finishing touches on the first issue of the Teenage Mutant Ninja Turtles comic book.