At first Ogo was a retainer of the Sasakis and Ochis. After the downfall of the Ochi family, (Wakayama Prefecture) (1573). When Hideyoshi Tovotomi was about to attack Mount Kaya with his large army, Ogo proceeded to Hideyoshi's headquarters at Saiga and concluded peace. Afterward, he directed the building of various Buddhist edifices including the Great Buddha Hall in Kyoto and the Chokokuji Temple in Yamato Province (Nara Prefecture) for Hideyoshi. Built the Kozanji Temple on Mount Koya and was accorded the title of Mokujiki Kozan Shonin. He was entrusted by Hideyoshi with the task of rehabilitating the Buddhist institutions on Mount Koya When Hideyoshi died (1598), he directed his funeral proceedings and also contributed to the building of the Toyokuni Sh1·ine dedicated to him. When the Toyotomi forces were defeated by the Tokugawas in the Battle of Sekigahara (1600), he fled to the Handoji Temple in Omi Provmce.
His name of Mokujiki (Tree Eating) derives from the fact that he lived on farms, berries and nuts instead of rice and vegetables since he became a priest.