object(Army)#1 (1) {
  ["units":"Army":private]=>
  array(2) {
    [0]=>
    object(Archer)#2 (0) {
    }
    [1]=>
    object(LaserCannonUnit)#3 (0) {
    }
  }
}
object(Army)#4 (1) {
  ["units":"Army":private]=>
  array(3) {
    [0]=>
    object(Archer)#5 (0) {
    }
    [1]=>
    object(Archer)#6 (0) {
    }
    [2]=>
    object(Archer)#7 (0) {
    }
  }
}