This Knightmare Frame appears in the Spin-off Manga Nightmare of Nunnally. The GX 01 piloted by Sancia is responsible for leading the Irregulars in combat as it is created to fit the role of its pilot as the Leader of the group. Sancia's GX 01 seems to be the Knightmare Frame that has undergone the most improvement of the group, as its Right Arm has been replaced entirely by an Anti Materiel/Knightmare Frame Rifle. In Combat, Sancia's GX 01 unit never strays too far away from Lucretia's, as Sancia and Lucretia provide supporting fire in combat while Dalque and Alice are responsible for hunting the enemy. The Knightmare Frame was Damaged by Cardinal Rolo's Geass, the Ice, when they turned against him.