There are legends and then there are legends, and writer Stan Lee without question falls into the latter category. Sadly, the man whose imagination has filled movie theatres, toy shelves, comics racks (hey, there used to be comics racks in stores!), and so much more with superheroes, has died at 95 after an alleged medical emergency. His legacy? Oh, things like Spider-Man, Iron Man, The X-Men, Ant-Man, Daredevil, Thor, The Incredible Hulk… it’s a really long list.

Born Stanley Martin Lieber on Dec. 28, 1922, in NYC, Stan began working at Timely Comics in 1939, the company which, by the early 1960s, had been rebranded Marvel Comics. Eventually made Editor-in-Chief, he was instructed to create a book that would cash in on the success of DC Comics’ Justice League, which brought together characters like Superman, Batman, and Wonder Woman, but rather than just throw characters from Marvel together, he decided to create something entirely new: The Fantastic Four.

This comic featured a quartet of heroes who had serious issues dealing with their newly-acquired abilities, fought with each other all the time, and came across as flesh-and-blood human beings as opposed to the “gods” that the competition was publishing. Take a look at Spider-Man’s alter-ego, Peter Parker, who was a teen trying to live by the mantra that “with great power comes great responsibility,” and failing as often as he succeeded. This became the trademark of Marvel Comics and the thing that put them on the map, which resulted in the so-called “Marvel Revolution” of the 1960s and gave birth to the heroes who have defined the superhero genre (for a microcosm of what Stan gave us, just watch Avengers: Infinity War — genuinely unbelievable).

Kim Kulish/Corbis via Getty Images

(Photo by Kim Kulish/Corbis via Getty Images)

In 1972, Stan stopped writing comics and was given the title of publisher. In 1981 he moved from New York to LA to oversee TV and film deals based on Marvel properties. Eventually, though, he was phased out from “active duty” for the company, though he remained the face most identified with Marvel for the rest of his life — despite starting various companies of his own over the years. His name appears in every Marvel film, and he shows up on screen as well in what have become famous cameo appearances. He was seen in the most recent film, Ant-Man & The Wasp, and there are rumors that he had filmed several more appearances before his death.

When asked by the Chicago Tribune about what caused him to ground his characters in real life, he replied, “That came mostly out of trying to write stories that I wanted to read. I didn’t enjoy stories that took place in a Gotham or Metropolis. I didn’t know where those places were! Why couldn’t it be a New York, Chicago, LA? For me, to enjoy what I was writing, I needed a superhero story as realistic as I could make it. I never tried to write for other people. I liked people who had problems I might have, because we all have insecurities, regrets. I like heroes who were not 100-percent perfect, who have things to take care of.”

In his life, Stan took care of plenty, spurring our collective imaginations in the process. RIP — we’ll miss you.