private ManaCost subtractMultiple(SpellAbility sa, String[] cost, ManaCost m) {
        for (String s : cost) {
            if (isEmpty())
                break;

            int num = 1;
            try {
                num = Integer.parseInt(s);
            } catch (NumberFormatException e) {
                // Not an integer, that's fine
            }

            for (int i = 0; i < num; i++) {
                if (isEmpty())
                    break;

                m = subtractOne(sa, m, s);
            }
        }
        return m;
    }