Hey guys! The reason you can't undo a move is that it would make the health mechanic obsolete. So you'd have to keep trying until you complete the puzzle. I think it would actually make the game alot harder, because there would be no feedback on wether or not you choose the correct color. Or if there was feedback, but no health mechanic, then it would make the game trivial. That's why I stick with this mechanic, which is by the way a ripoff of the Picross Madness game, found on this site /games/geardice/picross-madness
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