What is "aristion"

Aristion (died 86 BC in Athens) was a philosopher and tyrant of Athens from 88 BC to 86 BC. Aristion joined forces with Mithridates against the Romans under Lucius Cornelius Sulla in the First Mithridatic war, but to no avail. On March 1, 86 BC, Athens was conquered by Sulla and Aristion was executed. He is called Athenion by Posidonius, and he may be the same person, or he may be a second tyrant whose story became confused with the first.