I'm not sure how difficult it was to implement, but speaking purely as an outside observer, the tech for being able to draw/erase a finite amount of pixels on the screen seems like a really impressive feat to achieve within the timeframe of the jam. Like, it's really neat how if you use all your pixels and then erase like 4 of them, it only gives back 4 pixels you can draw in.
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Thank you for checking my game out! Admittedly the reason I was able to implement the drawing was because I focused purely on making it reality and put aside optimisations, so while it works, the resolution and hence the number of pixels you could draw was reduced heavily otherwise the game would brick up. So if I were to try again someday, I would defo approach it differently. :D