There must be 4 players for this to work. When the game starts the 4 of you will be split up. 2 of you will be in the room to the right and the other 2 will be on the room to the left.

When the game starts both players in the room on the right have to back out of the game. Then one person will have to stand in the corner of the main part of the room beside the door and a small boarded up hole in the wall.

The zombies will break open the barriers in the empty room and flood in. The zombies will then gather by the hole in the wall that the player is crouched beside and they will not move.

The other player must move into the small room near the staircase. Once inside the room you will be able to see a group of zombies in the room across from you.

The easiest way to kill the zombies is with grenades. Make sure that the player crouched in the corner has a weapon to take care of zombies that get into your room.

Do this until you get over run. When this happens exit through the stair case. Once the staircase barrier is open this becomes increasingly difficult to do.