Yuri Lowenthal
Ben Tennyson (voice)

Tara Strong
Young Ben Tennyson (voice)

Bumper Robinson
Rook Blonko (voice)

Paul Eiding
Grandpa Max (voice)

David Kaye
Cannonbolt / Heatblast / Khyber the Huntsman (voice)

John DiMaggio
Armodrillo / Fourarms (voice)

Eric Bauza
Dr. Psychobos / Diamondhead / Grey Matter (voice)

Ashley Johnson
Gwen Tennyson (voice) / Young Gwen Tennyson (voice)

Greg Cipes
Kevin Levin (voice)

Dee Bradley Baker
Crashhopper / Stinkfly / Spidermonkey / Wildmutt (voice)

Corey Burton
Malware (voice) / Malware / Mr. Bowman (voice) / Seebik (voice)

Rob Paulsen
Rhomboid Vreedle (voice) / Magister Patelliday (voice)

René Auberjonois
Azmuth (voice)

Charlie Adler
Hokestar (voice)

Dwight Schultz
Dr. Animo (voice)

Alexander Polinsky
Argit (voice)

Kevin Michael Richardson
Emperor Milleous (voice)

Kimberly Brooks
Serena (voice)

Tara Platt
Ester (voice)