Paul Ryan, a comic book artist for lengthy runs on several Marvel Comics titles, passed away Sunday. He was 66.

"It is with sad news I report the passing of my cousin Paul," wrote his cousin Chad Callanan on Facebook. "Chances are you were touched by him in your lifetime as he was the cartoonist for some of the most well known and beloved characters in the world. From Spider-Man, Thor, Iron Man, The Phantom to the Fantastic Four, most of which made it to the big screen and Hollywood. He was a true giant and artist, who achieved more success in his short life than any one of us would ever know in ten lifetimes. He was somebody who showed me how to dream big, but he was also my friend and that was good enough."

Ryan began a lengthy career with Marvel Comics in 1985 by inking two issues of "The Thing." He then landed his first ongoing series as penciler with "Squadron Supreme" in 1986. In 1987 he illustrated "Amazing Spider-Man Annual" #21 -- the wedding of Peter Parker and Mary Jane Watson. He then launched "D.P.7" with writer Mark Gruenwald as part of Marvel's "New Universe" line, sticking with that series until its end in 1989. Ryan then began simultaneous runs on "Avengers," "Avengers West Coast" and "Quasar." He penciled both "Avengers" titles until 1991, when he switched over to begin stints as the artist on both "Iron Man" and "Fantastic Four." Ryan made his mark on "FF" with a notable five-year body of work on the title.

Following his work with Marvel in the '80s and early '90s, Ryan turned in runs on "The Flash" and "Superman" for DC Comics. For the past decade, Ryan's work has been seen on the "Phantom" comic strip.