An artistic error or mistake, usually in the anatomy, but it can be in other elements such as composition or perspective.
This can be anything from the obvious: hands with too many fingers (post #1142825) or too many legs (post #71541), to more subtle errors: two left feet (post #1667989), or two mirrored hands like Tony Taka's disease (post #190107).
Do not confuse error with bad anatomy, bad proportions, bad hands, or bad feet, which are for elements that are merely poorly drawn, not outright mistakes.
Don't confuse error with error message.
Generally you should comment on the post describing the error when you find it along with tagging it with error.
The following tags implicate this tag: bad_reflection, wrong_feet, and wrong_hand (learn more).
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