The Sinister Six

The Sinister Six are a gathering of Spider-Man's most difficult foes. Over the years, The Sinister Six has taken on different members, leaders and expanded in size. The first incarnation of The Sinister Six was formed by Doctor Octopus in The Amazing Spider-Man Annual #1. The biggest branching out of the "six" would be the Green Goblin's "Sinister Twelve".

The Original Six
After several defeats at the hands of Spider-Man, Doctor Octopus figured it would benefit him to team up with some of Spider-Man's other foes. Doctor Octopus (who had his tentacles removed previously) mentally contacted his tentacles to come to him. He broke free of jail and contacted every foe that Spider-Man had fought to that date. Only Sandman, Vulture, Kraven, Electro, and Mysterio responded. Although Doc Ock tried to contact others like Doctor Doom (who was busy with the Fantastic Four), Green Goblin (who thought he could beat Spider-Man himself), and the Lizard (Kurt Connors had no vendetta against Spider-Man), the group remained.

Doc Ock formulated a plan to have each individual villain to fight Spider-Man at a specific location, in order to weaken him.

At this time Peter had lost his powers and started to return to a normal life as a student and photographer. However, The Sinister Six discovered Daily Bugle's secretary, Betty Brant, played an important role in Spider-Man's life and kidnapped her, as well as an innocent bystander, who turned out to be Aunt May. The Vulture told J. Jonah Jameson that if he wanted to save her, Spider-Man would have to face The Sinister Six. Peter overheard the conversation and, despite losing his powers, put on his suit.

He went to fight Electro at an electrical power plant. When he dodged one of Electro's bolts, he somehow regained his powers and won by simply shutting off the power. Electro dropped a card that led Spider-Man to Kraven who battled with wildcats and was defeated. Kraven's card led Spider-Man to Mysterio who used robots of the X-Men, but he too, was defeated. Then Sandman, who Spider-Man fought in an airtight box (that was meant to trap him as he touched the card) was rendered unconscious. Sandman's card led to Vulture who told Spider-Man not to use web-shooter while fighting him, so Spider-Man used a lasso. The final member and leader, Doc Ock, tried to sneak attack Spider-Man by removing his claws and when that failed, fought Spider-Man in a giant fishbowl in scuba gear to kill him as a real octopus. Spider-Man defeated all of The Sinister Six, who were jailed, Betty Brant and Aunt May (who didn't realize she was kidnapped and found Doc Ock charming) were saved.

Return of the Sinister Six
In the events of Amazing Spider-Man #334-339, five of the original members of The Sinister Six escaped to get revenge.

Kraven was the only one not present in the new group, having previously committing suicide (believing he killed Spider-Man, thus believing his purpose was over), so Doc Ock recruited Hobgoblin to replace him. With another 'A-Class' villain with the Six, Doc Ock felt his victory was assured.

This time Doc Ock's plan of taking down Spider-Man was part of a much larger plan of becoming master of the world. With Spider-Man out of the way, Ock believed, his creative genuis would be able to flourish into a master plan.

This time, instead of always taking Spider-Man one by one, tag teams sometimes occured. With Hobgoblin and Doctor Octopus together, the Sinister Six were much more powerful and Spider-Man was actually having problems fighting the Six. However, Sandman, now reformed, turned on the Six and aided Spider-Man in stopping the other five members, all who were sent to jail.

Revenge of the Sinister Six
In Spider-Man #18- 23 the group reunited once more, determined to follow Doc Ock's master plan of taking over the world, this time using alien weapondary. There once again was a swap Sandman for Gog (due to Sandman's betrayal). However, more sinister plans were already in place for the disbanded Sandman.

Sandman's foster family was hit by a bomb, which convinced Sandman it was because of his betrayal of the Six, so he coherced the other four (Gog was acting behind the scenes) to join him, and take down Doc Ock, as the group needed new direction. Doc Ock, having regained his adamantium arms from an unethical individual willing to sell them, overtook the group easily and turned the Sandman into glass. It turns out that Doc Ock wasn't the one who bombed Sandman's family, but the other five, knowing Sandman would think it was Doctor Octopus.

The other four, seeing they couldn't beat Doc Ock, rejoined him, went on a rampage and stole an arsenal of technology. In the process they defeated Spider-Man, The Hulk (in professor form), The Fantastic Four, Deathlok, Nova, Solo, Cyborg X, Sleepwalker, and Ghost Rider. Then, to Spider-Man's surprise, the Sinister Six moved on to a HYDRA base and committed mass murder there.

That was it for Spider-Man, who banded together with the other heroes defeated by the Six, and fought the Six. It was then Doc Ock revealed Gog, the giant, as the sixth member. Once again, the group was defeated and ended with Sandman's broken glass body shredding Doctor Octopus, almost killing him.

Sinister Seven
The Sinister Seven was formed by Hobgoblin in order to take down the rogue Kaine (a defective Spider-Man clone) who killed both Doctor Octopus and Grim Hunter. The new members in the Sinister group were Shocker, Scorpia, and Beetle. All feared that Kaine may come after them next (as he was killing Spider-Man's foes.

The group tracked down Kaine but Spider-Man came to Kaine's rescue. The duo took down The Sinister Seven.

Sandman's Sinister Six
Sandman came back from his glass imprisonment even more enraged then last time. This time he formed a new Sinister Six with Mysterio II, Kraven II and the original members besides Doc Ock, whom he replaced with Venom.

He was bent on revenge on Doctor Octopus once again, but the six were defeated by Spider-Man, Doctor Octopus (and ironically) Venom who accidentally went on a rampage almost killing Sandman, Kraven II, and Electro.