In this episode (the first of the second season), Victor Buono (perhaps most famous as BATMAN villain King Tut) plays a villain who's everything Aleister Crowley wanted to be: a magician with genuine ability who glories in being evil. He also heads a gang of assassins of varied talents (including Richard Pryor as a ventriloquist, although he has about one line and I think someone else voiced the dummy, who did most of their speaking) aptly known as the Eccentric. Their target is President Juarez, who got mentioned a lot in the series.
Manzeppi was also one of the few villains who got away, and even came back in a later episode. Unfortunately, he didn't come back again, unlike Dr. Miguelito Loveless (who admittedly was a greater villain, perhaps the best I've seen on TV).