Mithridates VI, King of Pontus (120-63 BC), AR tetradrachm in the name of Alexander the Great. Obv.: Alexander in lionskin of Herakles r., with the features of Mithridates of Pontus Rev.: Zeus seated l. with eagle, in Gk. characters LAK before, ODE beneath, BASILEOS ALEXANDROU.
This coin was probably struck 83-82 BC to help finance the Second Mithridatic War, one in which Mithridates of Pontus again took on Rome. We know these are his features in place of Alexander's, since there are other coins with essentially this portrait but bearing Mithridates' own title. Taking up the same parallel that this coin represents, Cicero, who should know, once described Mithridates as "the greatest of kings after Alexander" (Academica 2.1). His regionalist campaigns against Roman influence included an infamous synchronized slaughter of thousands of Romans abroad--the so-called "Asiatic vespers" of 88 BC--and the challenge of facing him down (which would take another 25 years) helped to weaken the Roman republic and bring Sulla to power. As a tactical hobby Mithridates not only learned numerous languages--22 by one count--but moreover grew famously expert in poisons, as Cowley remarks; having gained an immunity to every known poison, he at last had no choice but to call in a soldier to stab him. (Main source: Plutarch's Lives [Sulla, Lucullus, and Pompey].)