Frank Welker

Emperor Argall / Viltrumites (voice)

Fred Jones / Scooby-Doo (voice)

Baboons (voice)

Executive Vice-President (voice)

Lord Nibbler (voice)

Tough Street Dog / Mean Zoo Animals (voice)

Santa's Little Helper / Snowball II (voice)

Monkeys / Princess (voice)

Santa's Little Helper / Mr. Teeny / Hounds (voice)

Megatron (voice)

Alien Creature (voice)

Fred / Scooby-Doo (voice)

Fred Jones / Scooby-Doo / Baron Von Billfold (voice)

Nibbler (voice)

Tardigrades (voice)

Nibbler / Pygmy Hyena Moles (voice)

Mountain Lion (voice)

Raccoon / Plants (voice)

Manta Ray (voice) (uncredited)

Werewolf FX (voice)

Isis (voice)

Thug (voice)

Xenophages (voice) (uncredited)

Animals (voice)