Uhhh.. how can i say this...
*The idea is fine, and freaking creepy, but something failed in the making...
I think it's the global look of it when you look from afar, if you know what i mean.
*It seems like you've tried to depict the utter pain on the guy's face, and something like the ripping out of his lips, plus maybe the bottom part of his face's skin being stretched towards the bottom almost to the point it would get ripped apart. That's what i think i'm seeing.
*I think redoing the eyes, so that the stratching is more obvious, would remove some of the "cartoony" look that this icon surprisingly has somehow. And making the skin have more lines to show the mechanical tension it is suffering, if you know what i mean, would look great.
....
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Funny thing is, when i first saw the minimized icon in the icon list, it looked cartoony much, but the more i look at it, the more i see some real nasty twisted bad treatment lol...
Anyways, great icon idea.
EDIT: Nvm i think i know: the teeth are the fail. You need to look up a genuine anatomic mouth in wikipedia or w/e, because atm the angle, size and number of the teeth is uncorrect, and makes the picture unconsciously get classified unserious, hence cartoony. Imho.
EDIT2: I'll use the icon anyways, but better version is higher rating and just, more win.