In order to fight 20+ battles to get an epic chest a player has to play for ~ 7 hours and more. And that's inside one day. Not all people have so many spare hours in their days. Look what you've done with Amy. Could you let players themselves set the cycles in wich chests are reset? For those who wish it may be 24 hours, some others would like to play the 20 battles in several days or a week.