helpful, outrageous, unkind, terrible, galling, unethical, vengeful, sadistic, feral, vindictive, kind, vicious, atrocious, flagrant, honest, venomous, abominable, obdurate, unscrupulous, unprincipled, unforbearing, remorseless, unconscionable, cold, malevolent, forgiving, conscienceless, grim, unrelenting, revengeful, rancorous, oppressive, merciful, tyrannical
brutal (part of speech: adjective)
pitiless (part of speech: adjective)
resolute (part of speech: adjective)
earnest, deliberate, serious, staunch, willing, dogged, dauntless, headstrong, constant, relentless, resolute, strong-willed, committed, bold, intent, insistent, firm, unwavering, unshakeable, indomitable, steely, loyal, iron-willed, courageous, unflinching, persistent, inexorable, unbending, reliable, bullheaded, determined, unyielding, steadfast, resolved, stubborn, tireless, thorough, tenacious, plucky, steady, dedicated, set, stern, hearty, diligent, uncompromising, faithful, indefatigable, decided, decisive, true, fearless, strong-minded, persevering, zealous, valiant, devoted, implacable, unchangeable, spunky
insensitive (part of speech: adjective)
callous, hardhearted, hardened, indifferent, hard, stony, dispassionate, insensitive, heartless, objective, uncompassionate, detached, unfeeling, passive, aloof, numb, cold-blooded, unsympathetic, passionless, cool, blunt, anesthetized, tough, unconcerned, nonchalant, unemotional, emotionless, apathetic, hard-boiled
- Apparently the Germans had not used so many heavy guns in this region, or perhaps they had not yet become so desperate and ruthless as later on. - "A Journey Through France in War Time", Joseph G. Butler, Jr..
- But first we must punish our ruthless foe. - "Traditions of the North American Indians, Vol. 3 (of 3)", James Athearn Jones.
- But now Hilda saw Sarah Gailey afraid to go to London, and George Cannon pushing her forward with all the ruthless strength of his enterprising spirit. - "Hilda Lessways", Arnold Bennett.