From the looks of it, Spiederman will be infected by the symbiote for most of the film, then the finals scenes will involve the bell.
Anywho, I reckon the 4th bad guy may be the lizard. Why? Well, we saw the relevent one-armed doctor in spidey 2.
"Beer is the mind killer. Beer is the little death that brings total obliteration. I will face my beer. I will permit it to pass over me and through me, and when it has gone past I will turn the inner eye to see its path. When the beer has gone there will be nothing. Only I will remain."
Make beer, not war.