Add a new subrule to the Rule entitled “Battle”.  Call it “Time Freeze” and give it the following text:

While a Dragon is in a Battle, it cannot be trained under the Rule entitled “Training” and its subrules.  Whenever a Dragon leaves a Battle, whether it won or not, within 24 hours its Breeder may train it one extra time for each full day the dragon was in the battle.  For example, if a Dragon joined a battle at 9:00 on a Monday and Retreated at 20:00 on the following Thursday, its Breeder could train it two extra times.