If it's war she wants, cry havoc and let slip the sleuth hounds.
The first thing I knew I was sprinkling hell-fire on them, 'cry havoc, and let slip the dogs of war.'
To cry havoc appears to have been a signal for indiscriminate slaughter.
Do they in slumber enjoy again the midnight raid upon the marrow-bed, or cry havoc on the choicest lilies of the garden?
early 15c., from Anglo-French havok in phrase crier havok "cry havoc" (late 14c.), a signal to soldiers to seize plunder, from Old French havot "pillaging, looting," related to haver "to seize, grasp," hef "hook," probably from a Germanic source (see hawk (n.)), or from Latin habere "to have, possess." General sense of "devastation" first recorded late 15c.