When I made my grotesques I used vampire count crypt horrors. I thought they had the right body shape (narrow waists, hulking shoulders, lots of muscle) they may be the shape your after.
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"Whereas the duty of the Imperial Commander is either to seize or defend territory, the Dark Eldar make war only to steal. If, as a by-product of this, the are able to indulge their vile passion for murder, torture and other decadent acts, then they will joyfully do so, but this is not their primary goal"