Wise, stalwart, and comical, this middle-aged walking disaster makes other smile with no effort or notice. Lang Zan of Luoyang is Lang Shu's laid back uncle and advisor, and an unparalleled master of Zui Quan and second born of Lang Tao and Lang Jing Lei, his brother Lang Wen, Shu's father, being the first born. Never interested in the leadership of the Heaven's Fangs tribe, he helped his brother through support, input, and compatriotism. One day, Zan and Wen were approached by their human friend, Detective Jin Hai of Interpol. An criminal empire in Chengdu was strengthening their grip over the officers there, and Jin Hai was asked to find outside help. Zan and his brother agreed and traveled to Chengdu, where Zan volunteered for a sting operation, and infiltrated the ranks. When he worked his way up, he found himself being given more and more malicious duties, until finally the leader was within reach. He lashed out and blew his cover, unaware that his radio contact with Jin Hai and Lang Wen was lost. Zan was eventually subdued and prepared for torture. They started by digging into his face with a scalpel and pulling out his whiskers by the roots. Before they could complete their ruthless designs on him, Jin Hai and Lang Wen infiltrated the hideout and subdued the mobs leader and high-rankers.

Lang Zan walked away from the fight, or rather swayed. Without his whiskers, or any hope of them growing back, he walked like a drunkard, weaving and bobbing as he trod the earth. Once back home, safe in their mountain village of Luoyang, he began to train himself in the Long Fist style known as Zui Quan, better known as Drunken Fist, refusing to let his new handicap defeat him and force him out of the eternal fight against wickedness. Shortly after Wen took up the leadership, he first laid eyes on Huang Yun, the talented daughter of the village priest. Zan loaned his support and encouragement to his brother to try and charm her, and watched from afar as the love of his brother and this amazing she-wolf blossomed. He was overjoyed to become an uncle five years later, and watched his nephew grow like a second father. Less than a year later, Zan wandered far from the village, and stumbled upon a patch of exposed soil, in the dead of winter. He dug through and unveiled a Japanese Tanto dagger, encased in a red silk scabbard, with an oceanic sunset pattern sewn into it. Zan swayed back to the village, just as his own search party was assembling. He showed his new discovery, and pulled the dagger from the sheath, which caused the blade to release a blinding light. Once everyone regained vision, the scabbard laid next to a small fox kit.

Around its neck was a silk scarlet scarf. There was a brass case over the knot of the bandanna, and the Japanese characters, "Hiiro" and "Zuki" engraved on it. Yun read it softly, but Zan repeated it aloud for confirmation, which caused the kit to stir. Blind as most newborns are, the kit followed the sound of his voice, and leaned her head against his leg. Hirozuki was the name given to this kit, and Lang Zan adopted her as his daughter. He mastered the art after years of practice, and answered a new call of duty alongside his brother. America's Interpol knew of something brewing on the streets of Los Angeles, and Jin Hai arranged for Wen and Zan to board a plane to California. Their flight was compromised by an awful storm, and they arrived too late. When they finally arrived, a brazen and unbelievable bank robbery had occurred, right before their eyes. Two robbers wearing body armor, and equipped with a military grade arsenal, shot up the streets of L.A, and the two Lang Brothers were caught in the crossfire, doing their best to protect the innocent bystanders. One of the hundreds of bullets that tore through the air found their way to Wen's head, and the gunman who did it met the same fate only an instant later. In horror and shock, Zan was left vulnerable and knocked unconscious.

Awakening in an underground laboratory, he found his brother's body being prepared for dissection, a process that would expose the humans to the existence of the Langren. In a rage, Lang Zan broke free of the table to which he was strapped, and lashed out. He left the guards and scientists out cold, and escaped with his brothers' body. Sailing back to China, he carried Lang Wen's body all the way up to the Heaven's Fangs Village, and fell to his knees from exhaustion, unintentionally presenting his brother's remains to his sister-in-law, Lang Huang Yun, and thirteen-year-old nephew, Lang Shu. Their terrified expressions and cries of grief echoed in Zan's mind every night, as well as the vision of his brother's last moment. As a loyal little brother, he stood by his older sibling's side, sharing his life, but never making one of his own. Now with Wen gone, he had only begun to find himself, all while now assuming the duty of being alpha, which he never wished to bear. Four years passed, while he stood at Yun's side for her comfort, and helped Shu finish his training. On Shu's 17th birthday, when he was to assume leadership, Zan challenged him, to ensure he was worthy. Shu defeated him, with a punch that sent lightning through Zan's body. Shu had unlocked the hidden power of the Langren, as the first of the tribe to do so, and began training himself to use it.

Months later, Shu received a distress letter from a distant Langren in Aberystwyth, Wales. A monster was digging up graves in cemeteries all across Europe, and adding to them with those who visited them, ended by its hateful claws. Shu was convinced to embark, and Zan and his little Zuki, now 16, joined him. After weeks of tracking down leads with the Welsh Langren, Evan Langston, it was determined that a local street gang called the Red Talons, led by a powerful Langren gone bad. When it was clear that they were on their trail, Zan was attacked and beaten into a coma by the gangbangers. When he awakened, Evan told him that the monster was cornered, and Zuki disappeared in the fight, leaving behind a portal, and Shu leapt after her. Following the stories to the catacombs of the largest cemetery in Aberystwyth, Terfynol Crossfordd, he leapt through, after his beloved daughter and nephew. Zan is a peaceful spirit, though does all he can to humiliate his opponents when challenged, as is the purpose of Zui Quan and makes for great entertainment for him. Sympathetic and loyal, Zan sports the heartfelt grandfatherly air about him, and sees every ally through to the end.