Among the various rogues galleries of fictional characters, Spider-Man has one of the largest and most varied set of enemies in history. Even more dangerous, many of Spider-Man's villains take little issue with organizing into a group to combat him. The first, and most prolific, such group is the Sinister Six. Formed in 1964's Amazing Spider-Man Annual #1, Doctor Octopus was confidant where one villain failed to destroy Spider-Man, a group could finally do away with him. Contacting Doctor Doom, the Lizard, Green Goblin, Sandman, Electro, Vulture, Mysterio, and Kraven the Hunter, the last five answered the summons and formed the Sinister Six. In order to keep from stepping on each others toes, Octopus broke up the six members in different locations advantageous to the villain's skills and abilities and lured Spider-Man into playing the game by kidnapping the Daily Bugle's Betty Brant and Peter Parker's Aunt May (the latter caught up when she went to the Bugle looking for her nephew). Of course, Spider-Man wins the day and triumphs over his enemies. The group would retire for almost three decades. In that time, several villain teams cropped up.
Over in Japan, Toei's Spider-Man would face the Iron Cross Army lead by Professor Monster with Amazoness, Bella, the Ninders, and the Machine Bem. In America, the Sinister Syndicate was a mercenary group patterned after the Sinister Six made up of Spider-Man villains. Lead by the Beetle who brought together Hydro-Man, Rhino, Boomerang, and Speed Demon, the Sinister Syndicate was hired to protect the first Jack O'Lantern in Jason Macendale who was sought by Spider-Man and the mercenary Silver Sable. Successfully protecting Macendale, the Syndicate failed to kill their former foe due to the help, of all people, of Sinister Six founder Sandman. The Sandman began to reconsider operating as a villain after a cancer scare and traumatic experience merging with Hydro-Man to form the Mud-Thing. Separating back from his fellow Spider-Man villain, Sandman had a heart-to-heart with the Fantastic Four's the Thing (Sandman a founding member of the malicious Frightful Four battling the team of heroes) and decided to turn his life around. The former villain infrequently teamed with Spider-Man and soon after saving her, Sable decided to hire Sandman and formed the Outlaws (superhumans used to combat superhumans). Spider-Man having the unique distinction of many of his enemies reforming towards good, the Outlaws saw several former Spider-Man enemies group into a band of mercenaries with more altruistic motives. Alongside Sandman, there was Will o' the Wisp, Puma, Prowler, and Rocket Racer. When the Space Phantom initiated a conflict between Spider-Man and the Avengers, the web-slinger called in the Outlaws to help him in the situation. Following a Presidential pardon for the Sandman, the former villain and Spider-Man would be inducted into the Avengers as reserve members.
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