public ActionCommand(UnitKeeper target, Battlefield field)
            : base()
        {
            _target = target;

            _isDeadly = (_target.Changed != null && _target.Changed.Health == 0) ? true : false;

            _allies = field.FindAllies(_target.Original);
            if (_allies == null)
                throw new InvalidOperationException("Allies were not found.");

            _index = _allies.FindIndex(original => original == _target.Original);
        }