relentless

determined dogged ferocious fierce harsh implacable inexorable rigorous ruthless single-minded uncompromising unforgiving unrelenting unstoppable unyielding

adamant bound bound and determined dead set on go for broke grim hang in hang-tough hard inflexible inhuman mortal obdurate pitiless remorseless rigid stiff stop-at-nothing strict stringent unappeasable unbending undeviating unflinching vindictive

compassionate easy flexible gentle irresolute kind lenient merciful mild nice nonviolent peaceful remorseful sympathetic tame tender yielding

ending intermittent stopping understanding

incessant nonstop persistent punishing sustained tenacious unflagging unrelenting unremitting unstoppable

pertinacious unabated unbroken unfaltering unrelieved

intermittent relenting surrendering yielding

ending kind merciful stopping sympathetic understanding