—Lang's battle quote in Chapter 6 of Mystery of the Emblem
He is a general of the Archanean Empire and the Marquess of Adria. During the War of Shadows, he co-operated with Dolhr by betraying the Archanean royal family and killing the nobles who tried to fight back such as Noah, the Marquess of Menedy and father of Jeorge.  Lang then used his newfound position as Dolor's ally to steal wealth from civilians. At the war's end with Archanea's victory over Dolhr, Lang managed to avoid justice for his treachery by claiming to have been forced to side with Dolhr. During the War of Heroes, Lang was appointed the leader of the occupation army at Grust by Emperor Hardin (who was possessed by the Darksphere).
Lang's ruthless actions at Grust, including capturing all the young females, caused the civilians to rebel. Eventually Marth is summoned to Grust to aid Lang, starting with defeating the rebel leader Lorenz and securing the royal prince and princess, Jubelo and Yuliya. When the royal children manage to escape, Marth decides to fight Lang.
Lang retreats to Olbern castle, makes his subordinate Toras guard the castle to the death and even hires who he believes to be Navarre, but who is in fact Samuel. When confronted by Marth's army in his last moments, Lang pretends that his actions all came out because he was relunctantly following Hardin's wishes but it was merely a ruse.
Lang is a corrupt and deceitful man. He frequently abused his position as Marquess and later Grust Occupation General to steal possessions and lives from those under him. He seemed to have no restraint or mercy, planning to have the families of everyone involved in the Grust Rebellion killed, as well as plotting to kill the Grust's young heirs.
Lang appeared to have no loyalty to any side, willingly betraying his benefactors from Archanea, Dolhr, to the Emperor of Archanea to save his skin, whilst claiming his innocence. His casual cruelty made him disliked even among his own soldiers in the Grust occupation army.
—Lang's death quote in the original
—Lang's battle quote with the male avatar.
Lang is a Germanic surname and Chinese name which means "tall" in the former language and "wolf" in Chinese.
- In Mystery of the Emblem, Lang's portrait is an edited version of Jiol's. The only difference is that Lang is fully bald and his coat has a red trim. He is given a unique portrait in the DS remake.
- At the beginning of chapter, Lang mentions approaching reinforcements and plans to trap Marth's army in "a pincer attack". His strategy fits since he is holding Starsphere Cancer.