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Vios
Since: Feb, 2012
7th Sep, 2017 09:45:11 PM
Could it be Magic Mirror, by Zylom Games? It seems to fit your description fairly well — spot-the-difference, cartoonish art style, and a witch trapping people in mirrors. The official site is here.
I'm trying to find a game where a town is trapped in mirrors. I believe that it's a find a difference game mostly. One of the levels was in the dark. At the end of the game, I think you encounter a witch that tries to trap you in a mirror, only for it to back fire and trap her in a mirror. You have to save her. I think the art style is colorful and slightly cartoonish, at least in the cutscene just described.