There is an area in the tunnel space between Zone B and Zone C where the central wall separating the lower pathway from the upper pathway does not connect to the ceiling. Players can jump into this space and camp here, making travel through that section of the map nearly impossible, as they can simply back up and recover health while you attempt to jump up to get them, and then just gun you down. While they can be killed with AOE and explosives, it is very hard to remove players from that space with the average loadout. This needs to be patched, as it can be heavily abused in life based game modes.