90% sure this cat is Celozon's.
Oftentimes, pixel art is created with a maximum number of colors since the medium originated in old 8/16/32/64-bit games (who had 8, 16, 32, and 64 available colors respectively) which makes creating any type of gradient extremely difficult. While I can't go in and colorpick colors (since each possible teen is anti-aliased), this teen is the only one without gradients and appears to have potentially the fewest colors overall - especially since the highlight stands out more as colors that were too similar to each other were not often used in old game for the color limitation reasons. If Celozon wants to stay pure to the origins of pixel art for this outcome, I just don't see the other two cats growing into lower-bit images. Of course, last year their pet had a gradient, so this isn't the strongest reasoning ever, but at this point I'm not sure what else they could mean with all the pixel hints.
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