Post-Calamity War, Gjallarhorn started development of new mobile suits, but they were not for anti-Mobile Armor combat, instead they served as a deterrent for the new era. The EB-04 Geirail is a general-purpose mobile suit created in this process, it can trace its roots to the Calamity War era's Valkyria Frame and was deployed by Gjallarhorn as its main force before the EB-06 Graze was developed.

The Graze can be seen as a perfected form of the Geirail. The two machines have many commonalities, including basic control system and structure, and also shares the same concept, with the Geirail's high versatility and weapons augmentability being inherited by the Graze. After Gjallarhorn fully transitioned to the Graze, the Geirail was phased out and only a few remain in operation with regional Gjallarhorn organizations, while some others found their way onto the underground market and were subsequently deployed by other parties such as mercenaries. It can also be seen in the teaching materials provided by training schools.