On the glow-stone on the outside of the map there is a barrier 2 blocks high just so the soldiers can't get on there. Also I hope you enjoy this map I made, I'm planning on uploading more maps in the future. One thing you can do to release all of the soldiers at the same time is by setting up glass so they can't get out on all of the small huts in the corners. When your ready to start the match all you have to do is //removenear glass and to undo that you simply have to type //undo