Pre-existing characters used in Williams Street productions

In the early days of Williams Street, many characters were recycled for use in their shows from different Hanna-Barbera productions, this practice fell out of use after Aqua Teen Hunger Force.

Birdgirl (Judy Ken Sebben) Birdman and the Galaxy Trio "Birdman meets Birdgirl" (1967)

Harvey Birdman Birdman and the Galaxy Trio "X the Eliminator" (1967)

Black Widow Space Ghost "The Web" (1966)

Brago Space Ghost "Brago" (1966)

Brak Space Ghost "The Lure" (1966)

Creature King Space Ghost "Creature King" (1966)

Cyclo Space Ghost "The Cyclopeds" (1966)

Dr. Nightmare Space Ghost "Nightmare Planet" (1966)

Dr. Soonev Space Ghost "The Energy Monster" (1966)

Fred Flintstone The Flintstones "The Flintstone Flyer" (1960)

Jan Space Ghost "The Heat Thing" (1966)

The Lizard Slavers Space Ghost "The Lizard Slavers" (1966)

Lurker Space Ghost "Space Sargasso" (1966)

Mentok the Mind Taker Birdman and the Galaxy Trio "Mentor the Mind Taker" (1967)

Metallus Space Ghost "Homing Device" (1966)

Judge Hiram Mightor Moby Dick and Mighty Mightor "The Monster Keeper" (1967)

The Mind Taker Space Ghost "Jungle Planet" (1966)

The Moss Men Dino Boy in the Lost Valley "The Moss Men" (1966)

Moltar Space Ghost "The Ovens of Moltor" (1966)

Parko/Owlie Space Ghost "Space Birds" (1966)

Scooby Moby Dick and Mighty Mightor "The Sinister Sea Saucher" (1967)

Phil Ken Sebben Birdman and the Galaxy Trio "X the Eliminator" (1967)

Sisto Space Ghost "The Lure" (1966)

The Sorcerer Space Ghost "The Sorcerer" (1966)

Space Ghost Space Ghost "The Heat Thing" (1966)

Tarantapod Space Ghost "The Web" (1966)

Zorak Space Ghost "Zorak" (1966)