Man, what amazing art. Honestly the hand-draw style really makes this game what it is.
I think the way you ramp up the resource gathering is fantastically balanced. Did you guys actually playtest this or did you nail it first try? I think it's right in the middle between too forgiving and too grindy.
The audio (especially the lich's VA) was fantastic. I often see people throw on audio at the last minute as a sort of "oh shoot! sounds are a thing!" but it's clear you had a direction from the very beginning.
There was only one moment in the game that I was actually confused. After I got my first upgrade, I didn't really know how to access it (or that I could access it). I tried spam clicking on it, and I saw the confirmation bar fill slightly. Until the tutorial tip for holding the mouse click down appeared, I accessed my menus by rapidly mashing. Yeah... I'm not the brightest sometimes.
I would be interested to see what this game would look like with some colored-pencil textured colors, although I know that may take away a little bit from the hand-drawn aesthetic. I think it'd be worth a try!
Overall, this was a fantastic submission you should really be proud of. Great work!