fix your power rankings
Seriously. When my arena team gets one shotted by an opponent team that is half my power ranking, then the power ranking is utterly meaningless.
And I litterally men oneshotted. And no, they didn't even have a defence reduction debuff. First attack kills 2 of my team members. I go "huh?", then I pay attention and the 2nd attack deals around 60k damage oneshotting another of my champions.
That's appearantly a 55k power team with only 2 level 60'ies and 2 level 50'ies.
Nice balance and nice reliability of the power ranking.