Gender in speculative fiction
The first known female superhero is writer-artist Fletcher Hanks's minor character Fantomah, an ageless, ancient Egyptian woman in the modern day who could transform into a skull-faced creature with superpowers to fight evil; she debuted in 1940 in Fiction Houses "Jungle Comics".
X-ray vision
Among the best known figures with "x-ray vision" are the fictional Superman, and the protagonist of the 1963 film "X". The first person with X-ray vision in a comic book was Olga Mesmer in 1937's Spicy Mysteries. She is often considered to be one of the first superheroes. In myth, Lynceus of the Argonauts possessed a similar ability.