A couple of suggestions (and by the way, awesome game): 1) A button for a quick pause (like spacebar) 2) The ability to grind / replay missions for the credits 3) the ability to sell items 4) display hotkeys. Thanks for an awesome game!
There doesn't seem to be much of a speed difference between "Normal" and "Fast". Considering the constant grind of the levels, I suggest making "Fast" increase the speed by 50% to 100%, as opposed to the (10%?) it is now.
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