The show seems to be trying to ramp up the number of walkers and re-establish them as a proper threat to the survivors, after giving a lot of time over to more human enemies. Following on from the previous scene, we get one that shows huge numbers of them attacking some sort of container that looks like it has people inside. It does a great job of once again making them look scary and like a real threat. Also around this shot we see some fresh graves for the unlucky residents of Alexandria. There are four new spots, which is an indication of how many people will be dying in that particular attack.