Conversation so far:
who is the voice of finn in adventure time
Jeremy Shada voiced Finn on the animated television show Adventure Time.
who is the voice of jake in adventure time
Jake the Dog is voiced by John DiMaggio.
who else has john dimaggio voiced besides jake the dog
John DiMaggio's voice features as Bender on Futurama, some characters on The Mr. Men Show, Marcus Fenix in the Gears of War series, Dr. Drakken on Kim Possible, and more.

Question: has the voice actor ever appeared on-screen
Self-contained rewrite: has john dimaggio ever appeared on-screen