When you are doing a battle that is not PVP (meaning no timer on your or your opponents turn) you can exit the app and pick up the fight where you left off. You can strategically time an exit that gives you an advantage. If you exit the game when you have only two players and it is your opponents turn to attack they will only do 1 attack or any number above 1 as long as the additional attack points above 1 does not kill you if you block at least 1. Meaning as long as you put 1 point in block on your turn, wait for the game to say it is your opponents turn and then exit the game, when you restart the game it will ask you if you want to continue the battle or concede, select continue, the game will bring you back to the battle and your opponent will only attack up to an amount that will not kill you as long as you put one block down. Remember this only works when you only have two creatures left.