Knightmare Profile

Developed in secret with funding from Prince Schneizel el Britannia, the Siegfried is part of the clandestine research project Code R. Originally founded by Schneizel's late brother Clovis, Code R is dedicated to the research of individuals linked to the mysterious power known only as "Geass." The massive FXF-503Y Siegfried, classified as a "Knight Giga Fortress" rather than a Knightmare Frame, makes use of both the latest Knightmare technology as well as data from Code R. Rather than a standard cockpit, the Siegfried uses a special system wherein the pilot's nervous system is connected directly to the machine's control system, allowing for complete mental control. With the use of the Float System first seen on the Avalon and a number of verniers all over its body, the Siegfried boasts excellent mobility despite its size. Its only weapons are a set of seven conical slash harkens, but its tough construction and energy shields make it incredibly durable, capable of taking massive amounts of punishment without even cosmetic damage.

The Siegfried's first deployment was a pure accident, as Code R test subject Jeremiah Gottwald went into a psychotic rage upon hearing the voice of terrorist leader Zero (AKA Lelouch Lamperouge) and "appropriated" the machine in order to kill him. Despite his best efforts, including dropping a building on top of it, Lelouch and his IFX-V301 Gawain were unable to stop the Siegfried. In order to allow Lelouch to deal with a more pressing emergency, his accomplice C.C. (formerly the primary test subject of Code R) offered to fight the Siegfried on her own. The end of the battle saw both machines sinking to the bottom of the Pacific Ocean, their pilots still inside. The Siegfried is eventually salvaged by Britannia and, under the supervision of V.V., is upgraded with a boost to its offensive power as well as the installation of an electromagnetic unit for close defense. V.V. pilots the Siegfried when Lelouch leads an attack against the Geass Order's headquarters in China, but the machine is shot down by the combined efforts of Lelouch and his half-sister Cornelia. The scrapped Siegfried is then recovered by the Black Knights and modified into the Sutherland Sieg, for the personal use of Jeremiah.