resolute

active adamant ardent audacious bent bolder bold bound and determined brave bravest constant courageous dauntless decided decisive determined dogged earnest faithful fast faster fastest fighting firm game grimmest grim grimmer gritty gutsy hard-core hardheaded hard-nosed/hardheaded hell-bent immovable inalterable indomitable inexorable inflexible insistent intractable intractable/intransigent intransigent intrepid liege loyal manful more active more constant more intransigent more intransigent more intractable more intractable more hardnosed more hard nosed more hard-nosed more loyal more hardheaded more hardheaded more masculine more serious most hard-nosed most hardheaded most hardheaded most hardnosed most hard nosed most intrepid most masculine most intransigent most intransigent most intractable most intractable most loyal most serious persistent pertinacious purposeful secure serious set severe sobersided spirited stable steadfast steady stouter stout strenuous strong strong-willed sturdy tenacious tireless tough-minded tough toughest tougher true unbending unchangeable unchanged uncompromising undaunted unfaltering unflinching unmoved untiring unwearied unshaken unwavering weariless