Yuri LowenthalBen Tennyson (voice) Ashley JohnsonGwen Tennyson (voice) Greg CipesKevin Levin (voice) Dee Bradley BakerSwampfire / Echo Echo / Humungousaur / DNAlien (voice) Jeff BennettGhostfreak (voice) Richard McGonagleHighBreed / Forever Knight #5 / Sensei (voice) Kevin Michael RichardsonDNAlien #3 / HighBreed Commander / Big Ship (voice) Vyvan PhamJulie / Ship (voice) John DiMaggioRath (voice) Wil WheatonDarkstar (voice) Zeno RobinsonAlan / Heatblast (voice) David McCallumParadox (voice) Juliet LandauHelen (voice) Khary PaytonManny (voice) Robert David HallHighBreed Guard (voice) Corey PadnosCooper (voice) James RemarVilgax (voice) Tim CurryDr. Chadwick / Knight #2 (voice) Vicki LewisSerena (voice) Kevin ConroyBellicus / Warrior 2 (voice) Ioan GruffuddDevin Levin / Robot Guard (voice) Alexander PolinskyArgit (voice) Kamali MinterTrina / Zombie Girls (voice) Kim Mai GuestLucy / Zombie Girls (voice) Diane DelanoEdna / DNAlien #1 (voice) Will FriedleKen / Shem (voice) Rob PaulsenAlien Pilot / Cotton Candy Vendor / Patrolman (voice) George NewbernFrank (voice) Barbara BainVerdona (voice) Michael YorkPatrick (voice) Hakeem Kae-KazimConnor (voice) Clancy BrownDragon / Pilot (voice) James Arnold TaylorRaff / Attendant 1 (voice) J.K. SimmonsMagister Gilhil (voice) Don McManusCarl Tennyson (voice) Beth LittlefordSandra Tennyson (voice) Wallace LanghamTyler / DNAlien #2 (voice) Diedrich BaderSimian / Lu (voice) Dwight SchultzNull Guardian / D'Void (Dr. Animo) (voice) 
