Scathach is a formidable warrior and mentor in the Fate/Grand Order series, originating from Celtic mythology. Known as the 'Queen of the Land of Shadows,' she is renowned for her unparalleled combat skills and mastery over runic magic. As a Lancer-class Servant, she possesses the deadly spear Gáe Bolg, which she wields with precision and strength. In the series, she plays a pivotal role as a mentor figure to the protagonist, imparting wisdom and combat techniques to aid in the battle against formidable foes. Her enigmatic nature and stoic demeanor mask a deep sense of duty and honor.