Best known for his work writing DC Comics’ “Batman” and editing Batman titles from 1986 to 2000, O’Neil also worked at Marvel Comics on such series as “Spider-Man” and “Iron Man.” Over the course of his more-than-four-decades-long career in the industry, he was involved in the naming of the character Optimus Prime and in leading Batman back to a darker narrative. He also wrote episodes for TV shows “Batman: The Animated Series” and “G.I. Joe: A Real American Hero,” among others.

Following his death, family and friends flooded social media with love for the comic world legend.

“The saying goes that you should never meet your heroes,” Matthew Manning, a loyal fan of O’Neil’s work and a former DC Comics intern, wrote on Facebook. He recalled the overwhelming feeling of seeing O’Neil in the DC offices during his internship there. “To me, it was like walking past a movie star in the halls. This was the writer that redefined Batman in the 1970s. A writer whose work only got better with time,” Manning memorializes. “He never disappointed and always inspired. Denny O’Neil was the single most influential writer and editor to me as both a kid and an adult.”

Many credited the late great O’Neil, who also taught at Manhattan’s School of Visual Arts and wrote “The DC Comics Guide to Writing Comics,” for preserving the Dark Knight’s ongoing relevance.

“He was an absolute titan in the industry and one of its finest creative minds. I honestly don’t believe Batman would still be around today, and many other characters, if it hadn’t been for him,” another reader commented. “Godspeed Dennis O’Neil, thank you for the stories and for the inspiration.”

In addition to his influence on beloved characters, O’Neil is also recalled for his mentorship of fellow artists.

“He was a kind man with an acerbic edge, a giving soul, wickedly funny, and an incredibly talented writer who penned some of the greatest comic stories ever told,” wrote artist Bill Sienkiewicz.

“He took time out of work life to become a friend, one who generously gave of his personal time to talk from experience and of demons, to a young farm kid from New Jersey about the path of self-destruction [said] farm kid was heading down because of farm kid’s drinking. Not many folks will step up like that. Denny did, and I will be forever grateful.”