Митридат VI
The reason for this change is uncertain, but Mørkholm believes that when a group of Cappadocian nationalists revolted and promoted Ariarathes VIII of Cappadocia as king, Mithridates VI of Pontus suppressed the revolt ca. 95 BC, and placed his portrait on the coinage pronouncing his rule over the Cappadocians. In regnal year 13 and 15, which is 88/7 and 86/5 BC the drachms of Ariarathes IX show again a portrait of his father Mithridates VI of Pontus, during that time, the First Mithridatic War had started, and by placing his portrait on his son's coins he made their relationship perfectly clear to all beholders.