static public object Act_AddShieldingImproved(
            NetBattlefield bf,
            NetQueueItem q,
            List <NetQueueItem> stack,
            List <NetQueueItem> previousItems,
            MHRandom random)
        {
            NetSkill ns    = q.GetNetSkill(bf);
            NetCard  owner = bf.GetCardByID(ns.OwnerCardID);

            //skill needs target(-s)
            if (!NetTypeAtomic.IsValid(q.Targets))
            {
                return(null);
            }
            FInt extra = FInt.ZERO;

            if (ns.MainAtt != null)
            {
                extra = owner.GetSkillCastingStrength(ns);
            }

            FInt   value = ns.GetFloatAttribute("TAG-CA_SHIELD");
            string sign  = ns.GetStringAttribute("TAG-CA_SHIELD");

            if (value == FInt.ZERO)
            {
                if (bf.ChallengeType == EChallengeType.TypePhysical)
                {
                    value = ns.GetFloatAttribute("TAG-SHIELDING_PHYSICAL");
                }
                else if (bf.ChallengeType == EChallengeType.TypeMental)
                {
                    value = ns.GetFloatAttribute("TAG-SHIELDING_MENTAL");
                }
                else if (bf.ChallengeType == EChallengeType.TypeSpirit)
                {
                    value = ns.GetFloatAttribute("TAG-SHIELDING_SPIRIT");
                }
            }
            if (string.IsNullOrEmpty(sign))
            {
                if (bf.ChallengeType == EChallengeType.TypePhysical)
                {
                    sign = ns.GetStringAttribute("TAG-SHIELDING_PHYSICAL");
                }
                else if (bf.ChallengeType == EChallengeType.TypeMental)
                {
                    sign = ns.GetStringAttribute("TAG-SHIELDING_MENTAL");
                }
                else if (bf.ChallengeType == EChallengeType.TypeSpirit)
                {
                    sign = ns.GetStringAttribute("TAG-SHIELDING_SPIRIT");
                }
            }
            value += extra;

            value.CutToInt();
            if (sign == "*")
            {
                value = value * 0.01f;
            }

            foreach (var v in q.Targets.value)
            {
                NetCard target = bf.ConvertPositionIDToCard(v);
                if (target == null)
                {
                    continue;
                }
                FInt prev = target.GetCA_SHIELD();

                if (sign == "+")
                {
                    target.SetCA_SHIELD(value + prev);
                }
                else if (sign == "*")
                {
                    target.SetCA_SHIELD(value * prev);
                }
            }

            if (NetType.IsNullOrEmpty(q.SecondaryTargets))
            {
                return(null);
            }

            foreach (var v in q.SecondaryTargets.value)
            {
                NetCard target = bf.ConvertPositionIDToCard(v);
                if (target == null)
                {
                    continue;
                }
                FInt prev = target.GetCA_SHIELD();

                if (sign == "+")
                {
                    target.SetCA_SHIELD(value + prev);
                }
                else if (sign == "*")
                {
                    target.SetCA_SHIELD(value * prev);
                }
            }

            return(null);
        }