Seth Green as The Nerd / Batman / Robin / Scarecrow / Darkseid / Ace the Bathound / Toyman / Dr. Fate / Jimmy Olsen / Black Manta / Aquaman / Clayface / The Penguin / Killer Croc / Cyborg / Banehound / Various (voice)

Breckin Meyer as Superman / Bizarro (voice)

Nathan Fillion as Green Lantern / Black Adam (voice)

Alex Borstein as Wonder Woman (voice)

Matthew Senreich as The Flash / Reverse-Flash / Weather Wizard / Waiter (voice)

Alfred Molina as Lex Luthor / Green Arrow (voice)

Zac Efron as Superboy / Brainiac (voice)

Sarah Hyland as Lena Luthor (voice)

Clancy Brown as Gorilla Grodd (voice)

Paul Reubens as The Riddler / Sunbather (voice)

Giovanni Ribisi as The Joker / Two-Face (voice)

Kevin Shinick as Narrator / Starro / Captain Cold (voice)

Zeb Wells as Sinestro / Swamp Thing / Captain Cold (voice)

Tara Strong as Harley Quinn (voice)

Hugh Davidson as Martian Manhunter / Seahorse Leader (voice)

Clare Grant as Catwoman / Poison Ivy / Little Girl (voice)