* @param price The price to be charged for them.
     * @param cs A <code>ChangeSet</code> to update.
     */
    public void csAddMercenaries(List<AbstractUnit> mercs, int price,
                                 ChangeSet cs) {
        if (checkGold(price)) {
            createUnits(mercs, getEurope());
            cs.add(See.only(this), getEurope());
            modifyGold(-price);
            cs.addPartial(See.only(this), this, "gold");
        } else {
            getMonarch().setDispleasure(true);
            cs.add(See.only(this), ChangePriority.CHANGE_NORMAL,
                new MonarchActionMessage(Monarch.MonarchAction.DISPLEASURE,
                    StringTemplate.template("model.monarch.action.DISPLEASURE")));
        }
    }