Diarmuid appears in the light novel "Fate/Zero" and its 2011 anime adaptation as the Servant "Lancer", wielding his two spears, Gáe Buidhe and Gáe Dearg. While Gáe Buidhe retains its mythical ability of inflicting wounds that can never heal, Gáe Dearg is instead depicted with the ability to pierce magical defenses and negate certain magical abilities. Diarmuid's Lancer form returns in the mobile game based on the aforementioned series, "Fate/Grand Order", but can also be summoned as a "Saber" Servant and wields his dual blades, Beagalltach and Moralltach, rather than his spears. However, they hold a similar color scheme of red and yellow. Supplemental material for the light novel implies that Diarmuid's Master sought to summon him in the latter class.