MARVEL TEAM-UP (1972) #111

Spider-Man and the Devil-Slayer uncover the ancient myth of the Serpent Men! In the midst of stopping a crime, Spider-Man meets his Uncle Ben! But he turns out to be a Serpentine in disguise, part of a race of Serpents vowed to take over the Earth. Thus, Spider-Man teams up with the Devil-Slayer, but in the process, is dealt with a deadly Serpent bite that might very well kill him! To be continued in the next issue.