Ryōgen
Ryōgen (良源; 912 – January 31, 985) was the 18th chief abbot of Enryaku-ji in the 10th century.
He is considered a restorer of the Tendai school of Mahayana Buddhism, and credited for reviving Enryaku-ji. His supposed role as a precursor of the sōhei or "warrior monks" is questionable and seems to be a later invention.