private IEnumerable <ActionResult> CollectUnits(IArmy firstArmy, IArmy secondArmy) { List <ActionResult> collectedUnits = firstArmy.CollectKilledUnits(); collectedUnits.AddRange(secondArmy.CollectKilledUnits()); if (collectedUnits.Count == 0) { _gameEngine.EmptyTurns++; } else { _gameEngine.EmptyTurns = 0; } if (_gameEngine.EmptyTurns == MaxEmptyTurns) { _gameEngine.IsDeadHeat = true; } return(collectedUnits); }