Byster and the Great Discovery

Buster Bunny as Thomas

Sonic (from Sonic the Hedgehog) as Edward

Rotor (from Sonic the Hedgehog) as Henry

Knuckles (from Sonic the Hedgehog) as Gordon

Plucky Duck as James

Hamton J. Pig as Percy

Bugs Bunny as Toby

Calamity Coyote as Harvey

Fifi La Fume as Emily

Griff (from Sonic the Hedgehog) as Arthur

Banjo Possum as Stanley

123-Omega (from Sonic the Hedgehog) as Duncan

Melvin the Monster as Jack

C.L.I.D.E as Alfie

Mary Melody as Madge

Concord Condor as Harold

Willy Coyote as Cranky

King Acorn (from Sonic the Hedgehog) as Sir Topham Hatt

Queen Acorn (from Sonic the Hedgehog) as Lady Hatt

Babs Bunny's Mom as Ms. Jenny

Sonic & Sega All Star Racing Announcer (from Sonic the Hedgehog) as Mr. Percival

Axl Bull (from Tazmania) as Bill

Gator Bull (from Tazmania) as Ben

Shirley the Loon as Molly

Elmyra Duff as Mavis

Captain Squeege (from Sonic the Hedgehog) as Salty

Wakko (from Animaniacs) as Skarloey

Yakko (from Animaniacs) as Rheneas

Mr. Plotz (from Animaniacs) as Sir Handel

Mr. Skullhead (from Animaniacs) as Freddie

Amigo and Aiai (from Sonic & Sega All Star Racing) as Mighty Mac

Gladys and Gracie as Annie and Clarabel

Digeri Dingo (from Tazmania) as Rocky

Byron Basset as Terence

Little Beeper as Bertie

Tyrone the Turtle as Trevor

Silas' Minions as Max and Monty

Solley the Godpigeon (from Animaniacs) as Oliver (Pack)

Ralph (from Animaniacs) as Ned

Beaky Buzzard as Jeremy

The Mayor of Sodor as Himself

Babs Bunny as Rosie

Tazmania Devil as Whiff

Montana Max as Diesel

Danforth Drake as Arry

Roderick Rat as Bert

Dr. Gene Splicer as Diesel 10

Charlie Dog as Dennis

Lil' Sneezer as Peter Sam

Bookworm as Rusty

Arnold as George

Gotcha Grabmore as Elizabeth

Mater (from Cars) as Butch

Buttons (from Animaniacs) as Buster

Harriet as Henrietta

Squit (from Animaniacs) as Kelly