Steve Ditko, co-creator of Spider-man and Doctor Strange, was found dead in his apartment on June 29 and Ditko was believed to be dead for approximately two days before being found. The New York Police Department confirmed his death to the Hollywood Reports. No cause of death was mentioned.

The late artist was born November 2, 1927 in Johnstown, Pennsylvania. Steve began working on the now legendary Spider-man in 1961 when Lee, the editor-in-chief at Marvel Comics, gave Ditko the assignment after he wasn’t satisfied with Jack Kirby’s take on the idea of a teen superhero with spider powers. The look of Spider-Man — the costume, the web-shooters, the red and blue design — all came from Ditko. Spider-Man first appeared in Amazing Fantasy No. 15. The comic was an unexpected hit, and the character was spun off into The Amazing Spider-Man. Ditko helped create such classic Spider-Man characters as Doctor Octopus, Sandman, the Lizard and Green Goblin. Starting with issue No. 25, Ditko received a plot credit in addition to his artist credit. Ditko’s run ended with issue No. 38.

In 1963, Ditko created the surreal and psychedelic hero, Doctor Strange. The character debuted in Strange Tales No. 110, and Ditko continued on the comic through issue No. 146, cover dated July 1966.

Ditko left Marvel after a fight with Lee causing both of them to stop speaking to each other for several years. Ditko never explained his side, and Lee claimed not to really know what motivated Ditko’s exit. The best explanation is an assumption that Ditko was frustrated at Lee’s oversight and his failure to properly share credit for Ditko’s contributions to Spider-Man and Doctor Strange. The charismatic Lee was always the face of Marvel Comics, but Ditko (and Jack Kirby) thought Lee was more interested in self-promotion than selling the company, and, in the process, implied that he deserved the lion’s share of the credit for creating the characters in the Marvel Universe.

Ditko went on to work for DC Comics, Charlton and other small independent publishers before returning to Marvel in 1979, where he worked on Machine Man and the Micronauts. He continued to do freelance work for Marvel up until the 1990’s. Besides Spider-man and Doctor Strange, Steve Ditko is also known for his work on Creeper, Hawk and Dove, Mr. A, Question, Captain Atom and Blue Beetle.