Peter Cullen is a Canadian voice actor who is most well-known for his role as Optimus Prime in the Transformers franchise. Cullen also has experience producing animal noises and roars, and his sound effects have been frequently used in monster films.
- King Kong (1976) as King Kong (voice, uncredited)
- King Kong Lives (1986) as King Kong (voice, stock vocalizations)
- Gamera: The Brave (2006) as Toto (voice, stock vocalizations)
- When recording the roars for King Kong for the 1976 remake, Cullen strained his voice so much during a five-plus hour recording session that he injured his throat and began to cough blood. Cullen's vocalizations created for the film would go on to become very famous stock roars used in countless monster films across the world for decades to come.