Worked after I downloaded libpng16-16 on Linux mint
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Is this supposed to be gamepad only? The prompts seem to indicate so. And fire is Enter on the keyboard, which is weird to reach for.
Yeah, it's meant for controllers, but if you must the controls on the keyboard are the arrows, space to jump, enter to fire and q and e to dash.
Ended up just switching to controller, and the controls there feel pretty good :) (Wonky jetpacks aside ;P). Now I wanna go play some Megaman X XD