Following the Zimmad Company's first successful amphibious mobile suit, the MSM-03 Gogg, the Zeonic Company came back with its own original design. Using many internal parts from a standard MS-06F Zaku, the company produced the MSM-04 Acguy. Even with two Zaku powerplants, the heat signatures produced by the Acguy were relatively low compared to most other amphibious mobile suits from the One Year War. This lent the Acguy a stealthiness that made it perfect for covert operations. Zeon's Commander Char Aznable led a squadron of soldiers in Acguy mobile suits during a mission to destroy the mobile suit factory inside the Earth Federation's underground Jaburo base on 30 November UC 0079. Though the demolition mission was a failure, the Acguy did prove its usefulness by allowing Char's troops to succesfully infiltrate the base undetected. The Acguy's armament also proved something of a surprise to the Federation: in addition to head-mounted vulcan guns and rocket launchers in the left arm, what appeared to be more rocket launchers in the right arm were actually extendable claws. Topped off by a mega particle cannon, the right arm could also extend out, making it a useful punching or striking weapon. This is just standard loadout, as the forearms are interchangeable. Thus, there are some Acguys with rocket launcers in the right arm. Some have been seen to have machineguns instead of mega particle cannons, but that is most likely just an 'in-field' modification.