Technology & Combat Characteristics

A highly customized Gunpla built and piloted by Touma Aizen, it is based on the YG-111 Gundam G-Self (and YG-111 Gundam G-Self Perfect Pack), it also uses parts from the RX-0 Unicorn Gundam 02 Banshee. It is mentioned as one of the strongest Gunpla participating in the inter-high school tournament.

History

The Code ϕ was built by Touma Aizen sometime after he transferred to Gokusode High School. It was used by Touma during the inter-high school tournament, but he was defeated by the Protagonist in the finals. Touma would also incur another loss against the Protagonist in the following Winter Cup.

In preparation for the next year's Spring Invitational the Code ϕ is given a tune-up by Yotsuba Electric, the sponsors of Gokusode High School's Gunpla club, which included the addition of a customized Perfect Pack. The tune-up, in reality, was a support AI developed by Yotsuba Electric to support the player, and using it made Touma uneasy. Although Touma was able to defeat the Protagonist in practice by using Yotsuba Electric's AI support installed in the Code ϕ, Touma's pride precluded him from using the AIS during an official tournament and he lost against the Protagonist in the finals for the third time. The Code ϕ was repossessed by Yotsuba Electric to protect their AI support from being exposed.