What steps will reproduce the problem? 1. Run a milling deck! Woe! 2. Keep track of the number of cards your opponents have.

What is the expected output? What do you see instead? I guess we just want something like how MTGO does it: a deck icon overlaid with a number. Tapping the deck icon lowers the card count by one, and press-hold the deck icon lowers it by five?

Maybe this would be better in the mana pool / spell counter activity?