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- Eric Idle (Wreck-Gar in The Transformers: The Movie, Devon in Quest for Camelot, Dr Vosknocker in South Park: Bigger, Longer & Uncut, Merlin in Shrek the Third, and Spig in Delgo (film))
- Jason Isaacs (Zhao on Avatar: The Last Airbender)
- Steve Irwin (Bad Parent Hunter on Fairly OddParents, Trev the Elephant Seal on Happy Feet)
- Chihiro Ishiguro, a Japanese voice actress.
- Michael Ironside (Sam Fisher in the Splinter Cell games, Darkseid on Superman: The Animated Series)
- George S. Irving (Heat Miser on The Year Without a Santa Claus and A Miser Brothers' Christmas, The Narrator and Tap Tap the Chiseler from Underdog, Running Board from Go Go Gophers, Geppetto from Pinocchio's Christmas, The Captain from Raggedy Ann and Andy)
- Mako Iwamatsu (Aku on Samurai Jack, Iroh on Avatar: The Last Airbender, Splinter from TMNT)
- Bret Iwan (the current voice of Mickey Mouse (2009-current)
Read more about this topic: List Of Voice Actors