A mysterious virus called the "Yellow Zombie Virus" has been spreading across the land for the past several years, and the infected, who lose their self of self, start attacking Mobile Suits one after the next. In order to protect themselves from the infected, the remaining Mobile Suits are forced to live inside city strongholds. However, behind the fortifications, after the death of the former lord, the lord Dong Zhuo is as domineering as can be. As if led by fate, after meeting Guan Yu Nu Gundam and Zhang Fei God Gundam, Liu Bei Unicorn Gundam resolves to save the world.

Source: crunchyroll

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Other: Kidou Senshi SD Gundam
Other: Kidou Senshi Gundam
Other: Kidou Butouden G Gundam
Other: Kidou Senshi Gundam Unicorn
Sequel: SD Gundam World Heroes