The Agrissa is a large multi-legged mobile armor developed and used by the AEU during the 5th Solar Power War. This mobile armor is an example of a 'Buddy Craft', a type of support-use carrier vehicle that primarily docks with the lower half of a mobile suit, granting it highly specialized capabilities at a mobile armor level. While the AEU has an edge in this technology over the other factions, it was deemed that further development of the buddy craft would not confer the bloc much prestige.

The Agrissa can surround an enemy machine with its six legs and deploy a powerful plasma field that causes great harm to the enemy pilot, allowing the capture of the enemy machine. It also has another powerful weapon in the form of a plasma cannon, and a special coating is applied to the mobile armor's surface for resisting its own plasma weaponry. Two spike-like power receiver antennas are located on the mobile armor's top surface, they allow it to be supplied with power from the solar power generation system via microwaves, thereby supporting the Agrissa's huge energy expenditure. When flying, the mobile armor's legs are folded on the sides.