Lan Yuan, also known by his courtesy name Lan Sizhui, is a prominent character in the series 'Mo Dao Zu Shi'. He is a kind-hearted and diligent disciple of the Gusu Lan Sect. Raised by Lan Wangji, Lan Yuan is known for his gentle demeanor and strong sense of justice. Throughout the series, he plays a vital role in bridging the past and present, often reflecting on the legacies left by the older generation. His character embodies the values of loyalty and compassion, making him a beloved figure among fans.