Thanos is a fictional comic book super-villain appearing in publications by the American publisher Marvel Comics. Created by writer/artist Jim Starlin, the character first appeared in The Invincible Iron Man #55 (cover dated February 1973). Thanos is one of the most powerful villains in the Marvel Universe and has clashed with many heroes including the Avengers, the Guardians of the Galaxy, the Fantastic Four, the X-Men, and among many others.