In the last days of AC 195, as the conflict between Earth and the space colonies draws to a close, former OZ commander Treize Khushrenada rejoins the fray as leader of the terrestrial World Nation. To lead his troops into their final battle against White Fang's army of mobile dolls, Treize creates a suitably impressive personal mobile suit.

Treize's Tallgeese II was assembled from spare parts left over from the development of the original Tallgeese. This mobile suit was technically identical to the original OZ-00MS Tallgeese used by former OZ pilot Zechs Merquise, and it's a testament to Treize's superb skills as a pilot that he is able to control this notoriously dangerous mobile suit. Aside from its personalized color scheme, the Tallgeese II's only noticeable design change is to its head, which sports a Gundam-influenced faceplate with a "plume" on the head, and an Epyon-style crest.

Source: Gundamproject.com, New Mobile Report Gundam Wing