Sonic the Hedgehog/Transformers: Heroes United

Sonic the Hedgehog/Transformers: Heroes United is an upcoming crossover TV special.

Characters

 * Sonic the Hedgehog (Roger Craig Smith)
 * Miles "Tails" Prower (Colleen Villard)
 * Knuckles the Echdina (Travis Willingham)
 * Amy Rose (Cindy Robinson)
 * Shadow the Hedgehog (Kirk Thornton)
 * Optimus Prime (Peter Cellun)
 * Warpath (Jamieson Price)
 * Bulkhead (Kevin Michael Richardson)
 * Ratchet (Jeffery Combs)
 * Jetfire (Troy Baker)
 * Bumblebee (Will Friedle)
 * Ironhide (Keith Szarabajka)
 * Drift (Eric Bauza)
 * Prowl (Alan Tudky)
 * Arcee (Sumalee Montano)
 * Jazz (Phil LaMarr)
 * Smokescreen (Nolan North)
 * Elita-One (April Steward)
 * Sideswipe (Darre Criss)
 * Sunstreaker (Tom Kenny)
 * Bluestreak/Silverstreak (Charlie Schlatter)
 * Doctor Eggman (Mike Pollock)
 * Orbot (Kirk Thornton)
 * Cubot (Wally Wingert)
 * Metal Sonic
 * Megatron (Frank Welker)
 * Starscream (Steven Blum)
 * Thundercracker (Sam Riegel)
 * Skywarp (Tom Kenny)
 * Shockwave (David Sobolov)
 * Soundwave (Isaac  C. Singleton, Jr.)
 * Lugnut (David Kaye)
 * Knock Out (Daren Norris)
 * Smokejumper (Crispin Freeman)