Harry Osborne- In the comic books, Harry develops an addiction to heroine, and eventually stumbles upon one his father’s lairs. Being completely insane, he dons the Goblin garb and goes after Spider-Man. This would make sense, based on the ending of Spider-Man 2.
Probability: High
John Jameson- This astronaut is effected by some sort of ray in outer space, which transforms him into the Man Wolf whenever there is a full moon. Despite his inclusion in Spider-Man 2, it wouldn’t make for a very good finale, as this villain is relatively unknown.
Probability: Low
Scorpion- A petty thief is hired by J. Jonah Jameson to wear this mechanical suit, which allows him to easily stalk Spider-Man. Scorpion eventually turns on Jameson as well. He may be able to carry a movie by himself, but might make a better side villain with Harry in the lead.
Probability: Medium
Dr. Connors- This character is introduced as one of Peter’s professors in the movies, but in the comic books, he plays a war veteran who lost his arm, and seeks a way to regrow it by experimenting with reptiles. His experiments turn him into a raving Lizard man. But in the movie, the man has both his arms, which would cancel out his motive.
Probability: Low
Venom- As much as you would all like to see this, it will never happen. Venom is owned by another movie studio, and it would take at least two movies just to set him up. It was an entire saga in the comic book world, which meant it took years to complete.
Probability: Low
Hobgoblin- In the comic books, he is just a thief that just happens to stumble upon one of the many Green Goblin lairs throughout the city. He’s kind of a wimp when it comes right down to it, so the original gets killed, but there are a few more to take his place. But then again, Raimi might decide to make Harry the Hobgoblin to differentiate from the first movie.
Probability- Medium
Doctor Octopus- Of course it’s a long shot, but Ock goes quite a while in the comic series before he kicks the bucket. He was always one of Spidey’s greatest villains, and it’s a shame to see him go in the movie. I would have preffered to have him been arrested, and placed in some weird cell like Magneto was in X-Men.
Probability: Low
Miles Warren- If tradition continues, this would make sense since this was one of Peter’s idols. However, none of the characters necessary have been introduced yet, such as Gwen Stacy, and the Clone Saga was an insanely huge part of Spider-Man history, so there’s no way to tell it.
Probability: Low