I get the option to buy characters that I already have 7*. How hard could it be to program the Shard Shop to only display characters for purchase that the player doesn't already have maximum 7*?
I think the OP's idea on the shard shop is a good one. The shard shop would be substantially more useful if it wasn't always cluttered with characters we've already 7-starred. I find myself with shards and nothing to spend them on.
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