Great Lungmen, or more simply Lungmen, is a nation in the world of Arknights that is parallel to real-life China, but politically similar to a mix of Hong Kong, Shanghai, Tokyo, and Singapore. Wei Yenwu is the leader of the nation, and Ch'en acts as its head of security. Great Lungmen is known to be particularly harsh towards the infected, restricting them to the slums to keep them from infecting other citizens. An Annihilation Mode stage is set in this nation.
The Rhodes Island operators extracted the Doctor from the Ursus Empire to Great Lungmen, where they then propose a cooperative relationship. Wei Yenwu asks that Rhodes Island extract Misha for him with the help of Ch'en and Rhodes Island's allies (operators from BlackSteel Worldwide and Penguin Logistics), although the details of the extraction are kept confidential.