Power - Turn on the power.
Pods - Now when you kill zombies some will drop command cylinder for you to pick up. go up the stairs in the power room and place the cylinder in the control center right up the stairs. Once you do that go outside and look for a green beam in the sky. Go over to that beam. There should be a pod there which you will have to defend. When you finish the defense go to the pod and it should open in the middle with and item for you. The next cylinder will be the supply depot cylinder. Go to the big building that is broken down and it is like a mansion and place it in the small machine that has in green screen next to one of the doors. Go look and defend the pod again. The final cylinder will be the tank factory code cylinder. This is located at the giant robot and where there is a ledge. Place the cylinder in the machine with the green screen to the right of when you walk up the stairs when your in that room. Go look and defend the pod again.
Dragon - Go down to the operations bunker which is the flooded room and place the cylinders in the machine in there. Now go to any location where you inserted a cylinder and call in the dragon. Once the dragon arrives you can now ride it to the pack-a-punch room.