If they make a prequel game, who should be the final boss?

An Origins game i feel would be a great entry on the franchise, exploring past relationships, fleshing out more our favorite characters and would ease up some of the stuff done on SP2. With that said, who you want for the big bad?

I think Vulture, Scorpion or Electro would be great thinking on the boss battles, i like Kingpin as well, but i feel he's more fitting to be the big boss of a Punisher or Daredevil game. I would like a big bad to be super powered or at least feel somehow enhanced rather than a regular bulky guy.