Why is sky arena such trash all of a sudden? I used to be able to do 8-9 (couldn't finish) before everyone got wiped, and now I'm fighting teams that are 2k+ power more than even my starting five at castle #5 or 6. By design, this game makes it so that a difference of 2k power on a team is really equivalent to the enemy team being twice as strong (or more), and so you'd have to throw 3-4 full teams of 6k power out to eventually take down an 8k power team. This really makes it pointless to even try, please put some more effort into the matching system.
Considering how quickly keys get used up and also how quickly chests can build up, you should add in more options to acquire keys. For instance, I think you should add in the option of trading in chests that you get in order to get one or two keys back.
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