How about instead of a fairly useless textbox (which has to be adding at least some resource overhead), you use that space to let us select if we want 1x, 10x, 25x upgrade so we can buy in bulk without having to hold down a key. Also, it'd be nice to have an option to 'buy at', rather than 'buy up to', and to see how much it would cost to get that upgrade. So, for example, if I wanted to buy enough Combo to put me at 10 from 2, it would tell me how much fortune I needed to grind, rather than just telling me that it's buying up to 0 because I have 0 fortune left.
I would like to see the roll button and results moved out of the sidebar, so that we can keep dice selected to upgrade and still roll. Otherwise, a fun concept.
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