public void execute() {
            CardList list = gloriousAnthemList;
            Card c;
            // reset all cards in list - aka "old" cards
            for (int i = 0; i < list.size(); i++) {
                c = list.get(i);
                c.addSemiPermanentAttackBoost(-2);
                c.addSemiPermanentDefenseBoost(-2);
            }

            // add +2/+2 to vanilla cards
            list.clear();
            PlayerZone[] zone = getZone("Muraganda Petroglyphs");

            // for each zone found add +2/+2 to each vanilla card
            for (int outer = 0; outer < zone.length; outer++) {
                CardList creature = AllZoneUtil.getCreaturesInPlay();

                for (int i = 0; i < creature.size(); i++) {
                    c = creature.get(i);
                    if (((c.getAbilityText().trim().equals("") || c.isFaceDown()) && c.getUnhiddenKeyword().size() == 0)) {
                        c.addSemiPermanentAttackBoost(2);
                        c.addSemiPermanentDefenseBoost(2);

                        gloriousAnthemList.add(c);
                    }

                }// for inner
            }// for outer
        }