Svengali

A sorcerer-type muppet, dressed completely in black with a black mustache, black hair, and black eyebrows.

He appeared in Episode 103: Joel Grey during the Comedy Tonight number. he sang one line, and was performed by Dave Goelz.

He later appeared in Episode 112: Peter Ustinov, where he kept turning a monster-like character into various things as she sang You do Something to Me.