Sonic Boom (Season 3)

Heroes

 * Sonic the Hedgehog (Craig Roger Smith) - One of the two main protagonists and co-leader of the Knothole Freedom Fighters.
 * Miles 'Tails' Prower (Andrew Dayton) - Sonic's best friend and a member of the Knothole Freedom Fighters.
 * Amy Rose (Mae Whitman in style of Katara) - A member of the Knothole Freedom Fighters who has a crush on Sonic.
 * Princess Sally Acorn (Tara Strong& Kath Soucie) - The princess of Mobotropolis, one of the two main protagonists and co-leader of the Knothole Freedom Fighters.
 * Nicole the Holo-Lynx (Mandy Moore in style of Rapunzel) - A highly advanced AI who can take a digital physical form. She is a member of the Knothole Freedom Fighters and Sally's best friend who was revealed in "The Truth" to once be alive.
 * Antoine D'Coolette (Troy Baker in French accent) - The boyfriend of Bunnie Rabbot and a member of the Knothole Freedom Fighters.
 * Bunnie Rabbot (Ashleigh Ball for Season 1 and Season 2, recasted to Jennifer Hale in style of Ashe in Season 3 onwards) - The girlfriend of Antoine D'Coolette,a member of the Knothole Freedom Fighters & Cream's Long Lost Sister.
 * Rotor Walrus (Chris Cox in style of Hawkeye) - A member of the Knothole Freedom Fighters.
 * Cream the Rabbit (Andrea Libman) - A member of the Knothole Freedom Fighters & Bunny's Long Lost Sister.
 * Cheese the Chao (Dee Bradley Baker) - Cream's best friend and a member of the Knothole Freedom Fighters.
 * Big the Cat (John DiMaggio) - A laidback fisherman and a occasional member of the Knothole Freedom Fighters.
 * Knuckles the Echidna (Matt Lanter in style of Anakin Skywalker) - A treasure hunter and the guardian of the Master Emerald, and co-leader of the Chaotix.
 * Vector the Crocodile (John DiMaggio in style of Jake the Dog) - The leader of the Chaotix.
 * Espio the Chameleon (Phil LaMarr in style of Samurai Jack) - A ninja and a member of the Chaotix
 * Charmy Bee (Max Charles in Season 1, Jacob Tremblay for Season 2 onward) - The youngest member of the Chaotix.
 * Mighty the Armadillo (Jesse McCartney in style of Roxas in Season 2-through-3, recasted to Michael Rosenbaum in style of the Flash for Season 4-and-Project A.D.A.M.) - Ray's older ally and a member of the Chaotix.
 * Ray the Flying Squirrel (Greg Cipes in style of Michelangelo) - Mighty's younger ally and a member of the Chaotix.
 * Julie-Su the Echidna (Kira Buckland) - A defector from the Nocturnus Clan and Knuckles' girlfriend.
 * King Acorn (J.K. Simmons) - The king of Mobotropolis and the father of Sally Acorn.
 * Rosie Woodchuck (Candi Milo) - A motherly figure to the Knothole Freedom Fighters.
 * Uncle Chuck the Hedgehog (Peter Capaldi) - Sonic's uncle and a fatherly figure to the Knothole Freedom Fighters.
 * Manic the Hedgehog (Will Friedle in style of Terry McGinnis) - Sonic's long lost twin brother.
 * Sonia the Hedgehog (Jessica Dicicco in style of Flame Princess) - Sonic's long lost twin sister.
 * Ben Muttski (Bumper Robinson) - Sonic's long lost pet dog.
 * Vanilla the Rabbit (Sara Ramirez in style of Queen Miranda) - The mother of Cream the Rabbit.
 * Lupe Wolf (Estelle) - The leader of his own team of Freedom Fighters.
 * Dulcy the Dragon (Cree Summer reprises her role) - A close friend of the Knothole Freedom Fighters.
 * Honey the Cat (Kate Micucci) - A fashion designer and a close friend to Amy Rose.
 * Mina the Mongoose (Grey DeLisle) - A rockstar and singer who is friends with Honey. She soon develops a crush on Sonic.
 * Relic the Pika (Tabitha St. Germain) - A friend of Knuckles the Echidna.
 * Fixit (David Kaye in style of JARVIS) - The assistant robot to Relic the Pika.
 * Tikal the Echidna (Grey DeLisle) - The daughter of Pachacamac the Echidna.
 * Pachacamac (Phil LaMarr) - The father of Tikal the Echidna.
 * Shadow the Hedgehog (Loren Lester in Season 3, recasted to Vincent Tong for Season 4-5, and Nolan North in Season 6)- The Ultimate Lifeform created by Gerald Robotnik. He started off as a villain at the start of Season 3, but he has since become a reliable ally to the Freedom Fighters.
 * Rouge the Bat (Kathleen Barr for Season 3, Jennifer Hale for Season 4 onwards) - A jewel thief and accomplice of Doctor Eggman, who eventually works with G.U.N.
 * E-123 Omega (David Kaye in style of Beast Megatron) - A robot with a grudge against Dr. Robotnik.
 * Maria Robotnik (Mae Whitman) - The deceased daughter of Gerald Robotnik. She sacrificed her own life for the sake of her friend Shadow.
 * Blaze the Cat (Janet Varney in style of Korra) - A princess from another dimension.
 * Marine the Raccoon (Linda Callerini) - Blaze's best friend from another dimension.
 * Silver the Hedgehog (James Arnold Taylor for Season 4, recasted to Josh Keaton for the rest of the show) - A hedgehog from the future.
 * Professor Von Schlemmer (David Tennant in German accent) - An old friend to Silver the Hedgehog.
 * Gold the Tenrec (Kelly Hu) - A loyal ally to Silver the Hedgehog.
 * Commander Abraham Tower (Ron Perlman) - The leader of the G.U.N. Agency.

Villains

 * Doctor Ivo "Eggman" Robotnik (Mike Pollock)- The main antagonist of the series overall. An evil,mad but brilliant scientist who ruled as dictator of Robotropolis and the archenemy of Sonic.
 * Julian Snively (Tom Kenny) - Dr. Robotnik's nephew and his voice of reason, and typically the secondary antagonist.
 * Metal Sonic (Jim Meskimen in the style of Ultron) - A robot created by Dr. Robotnik that resembles Sonic.
 * Ixis Walter Naugus (Brian Drummond) - An evil troll sorcerer and former apprentice to King Acorn, as well as a fierce rival to Dr. Eggman.


 * Orbot and Cubot (voiced by Rob Paulsen and Jess Harnell, respectively) - Eggman's idiotic henchbots who are as bumbling as him.
 * Sleet and Dingo (voiced by Brock Baker and Brian Hull, respectively) - two assassins who work for Eggman.
 * Sara the Skunk (voiced by Malinda Kathleen Reese) - a mad skunk and Eggman's head scientist, being responsible for the creation of Nicole and Metal Sonic.


 * Wendy Naugus (Noël Wells) - An evil troll witch and the twin sister of Walter Naugus, who has a crush on Eggman.
 * Thunderbolt the Chinchilla (Grey DeLisle) - An apprentice to Dr. Robotnik.
 * Clove the Pronghorn (Laura Bailey in style of Black Widow) - An agent of Dr. Eggman, who made a deal with him to save her sister's life.
 * Cassia the Pronghorn (Mary Elizabeth McGlynn, Tiana Camacho for Season 5) - Clove's younger sister who was made into a cyborg by Eggman to save her life.
 * Connie Conquering Storm the Lynx (Sumalee Montano in style of Arcee) - A cyborg agent of Dr. Eggman, who styles herself after a ninja, much like Espio. She was once friends with Dulcy.
 * Nack the Weasel (Liam O'Brien in Australian accent) - The leader of Team Hooligan and a former member of the Chaotix.
 * Bean the Dynamite (Will Friedle in style of Deadpool) The wild card of Team Hooligan.
 * Bark the Polar Bear (Dee Bradley Baker) - The strong yet silent member of Team Hooligan.
 * Breezie the Hedgehog (Claudia Black, Kathleen Barr for Season 4, but back to Black in Season 5 onwards) - The head of Breeze Media.
 * Coconuts (Ian James Corlett for Season 2, recasted for Richard Ian Cox in style of Snails for all subsequent appearances) - The loyal robot butler of Breezie the Hedgehog.
 * Scratch (Gilbert Gottfried) - One of Breezie's robot employees.
 * Grounder (John DiMaggio) - One of Breezie's robot employees.
 * Scourge the Hedgehog (Josh Keaton in style of Major Ocelot) - Sonic's evil counterpart from Moebius, and leader of the Destructix, and later the Surpression Squad.
 * Fiona Fox (Nicole Sullivan in Season 2-through-3, Rebecca Shoichet for Season 4, Cree Summer covered for The A.D.A.M. Project) - Scourge's girlfriend and lieutenant, whom Tails is infatuated with. She later has a change of heart, becoming an ally to the Freedom Fighters.
 * Princess Alicia Acorn (Kath Soucie) - Sally's evil counterpart from Moebius, and the disgraced former princess of Anti-Mobotroplis. Also, an ex-girlfriend of Scourge.
 * Myles Prowler (Cathy Weseluck) - Tails' evil counterpart from Moebius, and rival to Scourge.
 * Rosy the Rascal - (Hynden Walch in style of Harley Quinn) - Amy's evil counterpart from Moebius and an ex-girlfriend of Scourge.
 * Doctor Ivo Kintobor (Dee Bradley Baker in style of Curt Connors) Eggman's good counterpart from Moebius, who's inventions help the world.
 * Buns Rabbot (Ashleigh Ball) - Bunnie's formerly evil counterpart of Moebius and a prodigy of Kintobor.
 * Imperator Pir'Oth Ix the Echinda (Tom Kane in style of Magneto) - The founder and supreme leader of the Nocturnus Clan. The main antagonist of Season 2.
 * Shade the Echidna (Nicole Oliver) - The captain of the Nocturnus Clan and cousin to Julie-Su and Lien-Da, who later defects with Julie-Su to the Freedom Fighters.
 * Lien-Da the Echinda (Kazumi Evans in style of Adagio Dazzle for Season 3, Grey DeLisle covered for certain episodes) - The general of the Nocturnus Clan and Julie-Su's older sister. She later joins Dr. Eggman as leader of the Egg Army.
 * Dr. Finitivus the Echinda (Troy Baker, Willem Dafoe in Season 4 onwards) - A mad scientist who defected from the Nocturnus Clan. The main antagonist of Season 3.
 * Dimitri the Echinda (Gary Chalk) - A former colleague of Dr. Finitivus who becomes possessed by Enerjak.
 * Enerjak (Jonathon Adams in style of Vaatu, Matt Lanter when possessing Knuckles) - A malevolent spirit hailing from the Twilight Cage, who is revered as a messiah by the Nocturnus Clan. The main antagonist of the second halves of Seasons 2 and 3.
 * Remington the Echidna (Milo Ventimiglia) - A cyborg fleet commander of the Nocturnus Clan and an old friend of Knuckles.
 * Jet the Hawk (Kyle Carrozza in style of Prohyas) - The leader of the Babylon Rogues.
 * Wave the Swallow (Kate Higgins reprises her role) - The brains of the Babylon Rogues.
 * Storm the Albatross (Scott McNeil) - The muscle of the Babylon Rogues.
 * Angelus the Babylon Guardian (David Kaye) - A security system created by the Babylonians.
 * Regina Ferrum (Claudia Black in style of Cheetah) - The self-styled Iron Queen and a rival to Dr. Eggman, and leader of her Iron Legion.
 * Gerald Robotnik (Steve Blum) - Dr. Robonik's late grandfather, and the creator of Shadow the Hedgehog.
 * Mephiles the Dark (Erik Dellums in style of Koh the Face Stealer) - An ancient and powerful dark spirit who seeks to kill Sonic and has connections with Shadow. The main antagonist of Season 5.
 * Black Doom (Hugo Weaving in style of Megatron) - The leader of the Black Arms. The main antagonist of the Season 3 premiere.
 * Doctor Ivo "Eggman" Robotnik Nega (Alan Tudyk) - The descendant of Dr. Eggman and the arch-nemesis of Silver and Blaze.
 * Nazo the Hedgehog (Edwyn Tiong reprises his role) - A mysterious and powerful god-like being bound to the Chaos Emeralds, drawing power from them, much like Shadow. The main antagonist of Season 4. He eventually reforms.
 * Chronos the Time Eater (Tim Curry) - An ancient, demonic cosmic entity with power over time.