I think it would be a great feature to be able to show only selected ranks and rarities when sacrificing champions, using some sort of filter (rough example below).

It would be even nicer to be able to mass upgrade champs with a feature similar to the "Combine All" in the Sanctum of Shards, but that seems technically challenging.  Plus, you probably want players to have to do some work to buff their champs, right?

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