Kraven The Hunter
Who should play him? Matthias Schoenaerts. Yeah, but you didn't see that coming, did you? If you're not sure who Schoenaerts is yet, and there's a fair chance you won't, check him out in Rust and Bone, Bullhead or Black Book. He's making his English language debut in Blood Ties, so you'll know who he is soon enough. As well as being a damn fine actor, the guy is massive. Like, really massive. It's ridiculous how comic-book-proportionate his physique is. Kraven can feel like a silly character, so you want someone truly intimidating in voice and physicality to play him. Schoenaerts is that man. I can't imagine anyone else in the role now I've thought of it. Anyone who's campaigning for Gerard Butler can get stuffed...
Why would/should they be included? OK, I'm basing a lot of assumptions on the fact that Andrew Garfield really wants him to show up, and he was part of the original Sinister Six line-up. I never liked Kraven, thinking little of him for his stupid costume and the fact he was just some nut with a net. But thinking about it, he seems a great choice of a villain, let alone for The Sinister Six. Imagine Moby Dick, but with Spiderman as the White Whale. The World's greatest hunter travels from afar to hunt down the most unbelievable Game that exists- a man with all the abilities of a Spider. Kraven is someone with stealth and cunning. Spiderman's used to taking on tortured souls or power-man egomaniacs- what if this cocky teen has to face off against a calm and collected soul who's only after one thing- his head? No thoughts of revenge on his mind, just a sole desire to take him down as Prey. Kind of like The Terminator, or Predator. Now, that would make a great standalone movie, but the concept is small enough you can slot it into a bigger story, and create a motivated character intriguing and enigmatic enough to expand within a bigger team in a later film. Including Kraven makes perfect sense, and that's why he should be included amongst other, more obviously cinematic villains. Kraven could well be the closest thing The Sinister Six has to a beating heart or an audience surrogate, and they is why he should be included, and like Rhino he can rock up without any backstory.
Likelihood: 2.5 out of 5 Considering he's not that fantastical a character, there's a chance we could get a challenging human antagonist that would ground the Sinister Six somewhat, but considering he's not that well known I doubt the creative team will let in someone who's not already wrapped up in the story arc of Oscorp, Ravencroft and Peter's parents. Still, it could happen...