heartlessly

ferociously fiercely mercilessly relentlessly ruthlessly savagely viciously

atrociously barbarically barbarously brutishly callously demoniacally diabolically ferally hardheartedly in cold blood inexorably inhumanely inhumanly meanly murderously pitilessly remorselessly something fierce something terrible unkindly unrelentingly

gently humanely kindly nicely

calculatedly callously coldheartedly coldly cruelly deliberately dispassionately indifferently intentionally premeditatedly ruthlessly unemotionally unfeelingly with full intent