Dionysus
From Tardis Wiki, the free Doctor Who reference
In Greek mythology, Dionysius (or Dionysus) was the son of Zeus and a sibling to Apollo, Athena, Artemis, Castor and Pollux, Hermes, Hebe, Minos and Persephone. (PROSE: Deadly Reunion)
In Athens, in 421 BC, Hex tried to pass himself off as the god Dionysus. (AUDIO: Mask of Tragedy)
The Cista Mystica was a Roman artefact used by the followers of Dionysus. (AUDIO: Dead London)
Behind the scenes
In reality, the name "Dionysius" is a nominalised adjective meaning "of Dionysus"; its use in Deadly Reunion as a name for the god himself is an error.