Scathach

Scathach is a legendary warrior queen and mentor from Celtic mythology who appears in the Fate series as a powerful Lancer-class Servant. Known as the Queen of the Land of Shadows (Dun Scaith), she is an immortal warrior who trained countless heroes, most notably Cu Chulainn. Scathach has transcended humanity and achieved a form of immortality that she views as a curse, as she can no longer die by conventional means. She is one of the most skilled spear wielders in the Fate universe, possessing combat abilities honed over millennia and the ability to slay gods and divine spirits.