Showing no mercy (8)
I believe the answer is:
ruthless
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">showing no mercy</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this in another clue)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for ruthless that I've seen before include "Lacking pity or mercy" , "Having no mercy like hustlers" , "Without pity or compassion" , "Hard-hearted" , "Callous" .)