Synonyms and related words :
atrociously, barbarously, bec et ongles, bestially, brutally, brutishly, cruelly, devilishly, diabolically, ferally, fiendishly, fiercely, inhumanely, inhumanly, mercilessly, pitilessly, ruthlessly, savagely, sharkishly, slaveringly, tooth and nail, truculently, unhumanly, viciously, wolfishly,