As Marvel's most iconic character, it was only a matter of time before Spider-Man joined the Avengers, Earth's Mightiest Heroes. For the past few years, the web-head has maintained a strong connection with The Avengers, in comics, movies and animation. It's funny to think, then, that it took decades for Spider-Man to become a full-fledged Avenger.

For the first few years of his existence, Spider-Man was a loner and an outcast. Peter Parker was also very protective of his secret identity, a trait that wasn't exactly conducive to being part of a team. The web-slinger received terrible publicity from The Daily Bugle, making him a mysterious and untrustworthy figure for other heroes.

In Avengers #11, by Stan Lee and Don Heck, Kang The Conqueror took advantage of Spider-Man's enigmatic image, creating a robot duplicate of the wall-crawler to infiltrate The Avengers. This Spider-Man impostor expressed a desire to join the team, before systematically defeating each of its members. Fortunately, the real Spider-Man arrived just in time to save his fellow heroes.

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Shortly afterward, in The Amazing Spider-Man Annual #3, by Stan Lee and John Romita Sr., The Avengers invited Spider-Man to join their ranks. As a test, Spider-Man was tasked with finding the Hulk and bringing him to the Avengers. The web-head succeeded, but, upon learning that the Jade Giant was really Bruce Banner, took pity on the Hulk and let him go.

Spider-Man didn't take another shot at joining the Avengers until Avengers #236, by Roger Stern and Al Milgrom. Upon learning that active members earn $1000 a week -- quite a lot in 1983 -- Spider-Man arrived at Avengers Mansion to request a full Avengers membership.

Before he could receive an answer, the priority alarm sounded, sending the Avengers to Project Pegasus. In an attempt to prove himself, Spider-Man stowed away on the Quinjet, joining the team on their mission. Although his teamwork skills left much to be desired, the wall-crawler was a great help in fighting off the invading Lava Men. The Avengers officially made Spider-Man a trainee member, impressed by his abilities.

Immediately afterward, the Rhino, Electro, Blackout, and Moonstone seized Project Pegasus' nuclear research dome, resulting in a confrontation with The Avengers. Moonstone ultimately set the reactor to self-destruct, but thanks to Spider-Man's scientific know-how, the reactor was safely shut down. This victory certainly earned Spider-Man a spot on the team, but the government later cited the web-slinger as a major security risk, forbidding his enlistment as an Avenger.

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Over the next few years, Spider-Man would occasionally team-up with the Avengers, even becoming a reserve member in Avengers #329, by Larry Hama and Paul Ryan. Yet the web-head didn't become a full member until New Avengers #3, by Brian Michael Bendis and David Finch.

During a prison breakout at the Raft, Spider-Man teamed with Captain America, Iron Man, Luke Cage, Spider-Woman, the Sentry and Daredevil to contain the chaos. Afterward, everyone except Daredevil stayed together, seeing this as an opportunity to reform the recently-disbanded Avengers. These New Avengers moved into Stark Tower, eventually joined by Wolverine.

Spider-Man enjoyed the luxuries of being an Avenger, even moving his Aunt May and Mary Jane into Stark Tower with him. Of course, after Civil War, Spider-Man was part of the outlaw Avengers, led by Luke Cage, once again making him a public enemy. Even so, Spider-Man was still an Avenger. Later, during "The Heroic Age," Peter got to be part of two legitimate Avengers teams. The web-head stood alongside the likes of Thor, Captain America and many others. Ever since then, Spider-Man has been part of the Avengers in one form or another.

It may have taken over 40 years for Spider-Man to become an official Avenger, but it's hard to imagine him away from the team since then.

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