Crows

The darker, more emo version of the Pigeons. Commonly found flying around graveyards and sulking in corners, these birds are the things that "taught" Father Grigori to aim and kill.
In garrys mod, these are most often spawned to be fed to barnacles, although they also make great target practice. Noobs think of the birds as some sort of race of higher beings, and create them by the hundred to worship them. This inevitably leads to the entire map being covered in shit, and leaves the noob with a whole lot of killing and cleaning to do.
They secretly plot to take over the world, and you can constantly see them watching you with their small, beady eyes.