So this is a file Joel has on him in the demo, it shows the stages of infection, including the second we had no idea about till now. The forth is ripped off, but i'm assuming its a totally covered in fungus thing, probably THIS.
So here is the note:
It says that Stalkers hide and surprise attack. I'd also like you point out that Joel in the demo calls the 'rooted' infected (the one against the door) a Clicker. From this i assume that when they lie down and root to spread the infection, it isnt counted as a phase.
are you sure? I thought it was big m**** f*****?
sumone called it big metal thingy.
I called it Metal gear.
The document doesn't show anything about the Stalkers except for the picture (which you can see in the OP) and a sentence saying 'Uses environment to hide and ambush victims. Will frequently flank and attack from behind. Approach with caution and check your surroundings'