Grey-Glider wrote At level 10, the worst place the box could be is in the main room, because the Zombies will come at you from all sides, and virtually you won't survive past level 10, unless all 4 players are extremely good. When you get the teddy bear, you follow the box wherever it goes. But when you open the gate, the box will spawn in the main area, either downstairs or upstairs. But when you open the stair it never comes back to the main room... Only if the gate has been opened too.

Its hard to fight off until you get the teddy bear you say?
Actually, its not. Get one person on each side up stairs, fighting off the Zombies, fixing the windows etc. Get two people downstairs, doing the same thing, making sure that the Zombies don't go up the stairs. If you can manage to do that, then when the teddy bear comes, it will be a lot easier to follow the box around and survive.

Any questions, comments, concerns?