The ASW-G-08 Gundam Barbatos is the main mobile suit of the Mobile Suit Gundam IRON-BLOODED ORPHANS television series. The unit is primarily piloted by Mikazuki Augus.
The Gundam Barbatos is the 8th of the 72 Gundam Frames created by Gjallarhorn near the end of the Calamity War to counter the threat of the powerful mobile armors such as Hashmal. It was later discovered by Maruba Arkay in the Mars desert and was recovered to serve as a power reactor for Chryse Guard Security's base. The machine was taken out of the base by Mikazuki Augus during Gjallarhorn's assault. CGS, now Tekkadan, continued to improve the suit with parts and armor taken from defeated Gjallarhorn mobile suits. Teiwaz technicians later restored the Barbatos to its original appearance and close to its original performance.
Following the defeat of the Brewers, Barbatos' spare parts were used to transform the ASW-G-11 Gundam Gusion that Tekkadan had obtained from the space pirates into the ASW-G-11 Gundam Gusion Rebake. After the Montag Company offered their alliance to Tekkadan, the group gives them spare parts for Gundam Barbatos as a gift. These parts were used in Barbatos' subsequent forms, proving to be handy during the atmospheric entry battle and subsequent battles on Earth.
On Earth, the battle at Millennium Island with Carta Issue's forces resulted in Barbatos losing its shoulder armor, and they were replaced by those from a defeated Graze Ritter. It was also upgraded with new waist boosters. En route to Edmonton, Tekkadan met with Carta's forces again, but they were quickly dispatched by the Barbatos. At the outskirt of Edmonton, the Barbatos and Tekkadan's other mobile suits spent three days fighting with Corlis Stenja's forces. The enemy was eventually reinforced by Gaelio Bauduin's ASW-G-66 Gundam Kimaris Trooperand Ein Dalton's EB-AX2 Graze Ein, and the Barbatos was subsequently locked in a fight with the former. With help from McGillis Fareed and his V08-1228 Grimgerde, Mikazuki and Barbatos escaped from the Kimaris Trooper and heads to the city where it stopped the Graze Ein from killing Kudelia Aina Bernstein. During the fight with Graze Ein, Mikazuki was pushed hard and in order to win, he sought more power from the Barbatos via his Alaya Vijnana system. The system responded and improved his reaction speed, leading to Barbatos having better movements. The Barbatos' shoulder armor and backpack were later ejected as decoys, and the suit managed to slice off Graze Ein's forearms after Mikazuki mastered the Long Sword - the Barbatos' only handheld weapon left at that time. The Barbatos then won the battle after piercing Graze Ein's cockpit, killing Ein.
After the battle of Edmonton, the Gundam Barbatos participated in numerous battles for Tekkadan. However, its accumulated damage soon proved too much for Tekkadan's mechanics to repair. Thus, it was sent alongside the Gundam Gusion Rebake to the MS Workshop in Saisei to receive an overhaul, becoming the ASW-G-08 Gundam Barbatos Lupus.