Technology & Combat Characteristics

Built by Sei after the 7th Gunpla Battle World Championship, the Build Strike Cosmos is the culmination of all his Gunpla work up until then and is made to fit his battle style. Although visually identical to its predecessor, the GAT-X105B/ST Star Build Strike Gundam, the unique systems created by Sei were incorporated in a more refined manner. For example, the RG System was improved and a new feature known as the Absorb Field that seems to be an improvement of the Star Build Strike's Absorb System is added.

History

The Build Strike Gundam Cosmos was used by Sei Iori during the 8th Gunpla Battle World Championship Japanese Third Block Qualifiers. After the Build Strike Gundam Cosmos launched, its RG System was activated and its Absorb Field was deployed. The Gunpla then charges forward, leaving a colorful Plavsky Particle trail in its wake. It then remained as Sei's regular Gunpla for Gunpla battles.

Later, the Build Strike Gundam Cosmos was upgraded with enhanced RG System parts for an exhibition match in the newly built Yajima Stadium, which featured a new large-scale battle system designed by Nils Yajima. However, it was stolen by Mikio Mashita on the way there. It was then used by Mikio at the stadium to defeat Ricardo Fellini and his XXXG-01Wfl Gundam Fenice Liberta. Subsequently, it was placed under autopilot and fought against Sei and his SB-011 Star Burning Gundam. During the battle, Sei noticed the flaw of the Build Strike Gundam Cosmos, and used it to immobilize the Gunpla. This forced Mikio to deactivate the Build Strike Gundam Cosmos and used his Psycho GM.

After Mikio and the other Gunpla Mafia members were arrested, the Build Strike Gundam Cosmos was used by Sei in a battle with the Star Burning Gundam controlled by Reiji, fulfilling the promise between the two friends. The Gunpla was later upgraded into the GAT-X105B/GC Build Strike Galaxy Cosmos.