This article is for fictional characters from the Sonic the Hedgehog franchise that appear exclusively in the animated series Sonic Underground.
For minor characters in other continuities, see Other characters in Sonic the Hedgehog.
was a robot, an ape-like intelligence operative under Robotnik. He was assigned to oversee the production of Robotnik's spy watch robots, he first appeared while Sonic and Manic were busy destroying spy watches and captured them in an energy net but they escaped when Sonia severed the net and caused it to crash into N who was apparently destroyed, however he later appeared along with a portable Roboticizer and captured Manic, Sonia, Mindy LaTour and Mr. LaTour who was fleeing from the mansion but failed to catch Sonic who used the converted watches to shut him down permanently.
An ancestor of Queen Aleena Hedgehog
, Sonic, Sonia, and Manic, Aman-Rapi
was a sorcerer and prophet. In his own time, Aman-Rapi foretold the coming of Dr. Robotnik, and inscribed a blueprint on how to defeat him on a scroll which was placed in his tomb. Later, when Sonic and the others came looking for the scroll, Aman-Rapi's mummified minions mistook Sonic for him. The reason for this was revealed as the spirit of Aman-Rapi himself appeared, similar in appearance (except for an Ancient Egyptian
outfit) and personality to Sonic. After the Sonic Underground granted his request for a song, he used his spell of immobility to freeze the invading enemies long enough for them to escape. Unfortunately, the scroll was so old that when it was removed from its tube, it crumbled to dust. However, Aman-Rapi had left one message: inscribed on the tube was a hieroglyph which translated meant "Hedgehogs will prevail" or as Sonic put it "Hedgehogs rule".
Argus was Queen Aleena's bodyguard and was supposed to meet her, but was captured and roboticized. The siblings managed to free him briefly from his programming and he shows them where the meeting location with the queen. He fights for control over his body, but loses, but manages to save Sonic, Sonia and Manic from being captured.
One of Dr. Robotnik's most powerful creations, ART
was developed for the purpose of defeating the Sonic Underground and their Freedom Fighter allies. Able to absorb any technology into his frame to increase in size and power, ART is a learning robot, capable of adapting to anything his opponents might deploy. "ART" stands for "Artificial Robot of Technology".
ART was sent to capture the Hedgehogs, going through several form changes as he attempted to abduct them. Despite managing to thwart him several times, the trio were caught by ART while rehearsing for a concert. However, ART had heard them play, and requested a song. The group obliged, and ART's free will was activated by the music, even leading him to play a keyboard similar to Sonia's.
ART then defected to the Freedom Fighters, using his impressive abilities to free prisoners and destroy SWATbots. However, he and the Hedgehogs were later caught in a crushing chamber. Using his strength, ART blasted a door so that his friends could escape, but he himself was crushed. However, he also served to inspire Manic the Hedgehog, who at that time had been feeling as though the efforts against Robotnik were pointless.
Sir Bartleby of Dresdin
is a posh aristocratic mink
and one the richest civilians of Robotropolis. He was Sonia's fiance. Pompous in every sense of the word, Bartleby loves nothing better than drinking rosebud tea, and himself. Despite these shortcomings he cares deeply for Sonia's welfare, but thinks her brothers are a bad influence on her. Bartleby and Sonic have had to join forces at times, including helping Sonia get to the debutante
ball. In Bartleby the Prisoner
, Bartleby was announced an enemy to Robotnik and was put on trial as a trap for Sonia. The Sonic Underground helped him escape and he had to go into hiding to escape Robotnik's forces.
He shares an uncanny resemblance with Antoine D'Coolette from the Sonic the Hedgehog comics and "SatAM" cartoon. He even shares his personality.
is an elderly vampire bat
who is the caretaker
of Worst Castle, which is supposedly Sonia
's ancestral home. He has a pet owl
called Hooter who he is very found of. He cannot stand loud noises and is very humorous. His catchphrase is "I am Berlock, the castle caretaker." He speaks in the classic vampire accent. Berlock was forced by Sleet who "threatened to eat Hooter" into helping him set a trap for the Sonic Underground, but after confessing all to the hedgehogs, he helped them escape the castle through a dimensional mirror and survived the collapse of the castle. Berlock is actually an agent of Queen Aleena, as seen when he acknowledges her presence nearby.
is a sea sponge
who is the captain of the Queen Aleena
showboat. He runs the resistance cell at Port Mobius, and for a long time was the entirety of the resistance there. He speaks in stereotypical nautical slang. As a sponge, he also has the interesting ability of being able to absorb large amounts of water within his body. When the residents of Port Mobius turned to Robotnik's side so he could protect them from Moby Deep who was sinking ships (when it was actually a sub made to look like a sea monster) Squeege was the only one left as being part of the resistance. When the Sonic underground crashed into (literally) Squeege's showboat, he managed to persuade them into helping him catch Moby Deep. However, this ended up attracting attention from Sleet, who planned to destroy his ship. Sonic eventually arrived on the ship to help the others destroy the sub and help Squeege bring the rest of Port Mobius back into the resistance.
The pet of Knuckles the Echidna, Chomps is a carnivorous dinosaur with a blue underside and the top of his body being red. Chomps is the only other known inhabitant of Sonic Underground's Floating Island, and served Knuckles by devouring intruders who came onto the island. He wanted to eat Sleet and Dingo, but after Knuckles released them they ran away, leaving behind a holo-projector with falsfied images of Sonic, Sonia, and Manic planning to steal the Chaos Emerald. Chomps ate the projector, causing the images to appear out of his mouth and nostrils. Thanks to this, the Hedgehogs were able to determine why Knuckles was attacking them. Chomps only appeared in the episode Friend or Foe.
Interestingly, Chomps bears some resemblamce to the Biolizard - though of course Chomps was made long before the idea of the Biolizard was even conceived.
is a friend of the Sonic Underground, and one of that continuities Freedom Fighters. He is a lion
and has a high IQ. He is very similar to Tails
as he is a mechanical expert, appears to be intelligent and can fly vehicles. He is also a great computer hacker and inventor. Cyrus secretly worked for Robotnik to prevent his father from being roboticized, but Robotnik back-stabbed him and had his father, Lionel, roboticized. Cyrus betrayed Robotnik and stayed loyal to the resistance, helping the hedgehogs in several of their missions.
A big, orange creature, probably a dingo, Dingo is the dimwitted partner of bounty hunter Sleet from Sonic Underground. His outward demeanor denotes a tough person but he is quite soft deep inside. Hired by Robotnik to hunt down the royal family, Dingo quickly develops a crush on Sonia, which she often uses to her advantage. Dingo is also very gullible, doing whatever Sleet tells him, and frequently not understanding an insult or parts of a sentence.
Dingo's only real usefulness is in his odd ability to change shape. When Sleet presses the button on his remote, Dingo can turn into any solid object or lifeform.
Dingo's voice was done by Peter Wilds.
is a robotic hairdresser
created by Robotnik for gathering intelligence. The robot hypnotizes her patrons into revealing secrets which are then recorded by an internal cassette device. Sleet and Dingo periodically collect the tape and take it back to Robotnik. However the Do-Bot is unaware that she is aiding Robotnik and has no knowledge of the tape inside her.
was an odd insect-like creature and a major member of Mobotropolis' criminal underworld. Manic was taken by one of Ferrell friends that is when he accidentally became Manic's foster father and taught the hedgehog everything he knew about thieving. Like the rest of the triplets' guardians, he was roboticized.
(if you can) is the tribe leader of a desert clan. He has actually been half-roboticized and hides his mechanical limbs.
's foster mother. She was Roboticized. She appears on three episodes: Beginnings
, Harmony or Something
is from the episode "The Hedgehog in the Iron Mask".
His name is possibly a parody of the actor Luke Perry.
Manic the Hedgehog
Manic the Hedgehog is the brother of Sonic the Hedgehog and Sonia the Hedgehog. In the series, his instrument involves the drums. He also loves to surf. Although Sonic and Manic look a lot alike, his hair is more wild and his fur is green. He likes to steal things (and is rather good at it) and doesn't like to return what he has 'found'. The only thing he hates more than returning things is Dr. Robotnik. He loves kids too.
is the son of the chief of the Speedster Island tribe.
is a horse
who is the Mayor
of Mobodoon, the Sonic Underground band's hometown. She was impeached by Sleet, but it is presumed that she has resumed office.
is a pickpocket
who leads a small group of thieves. After helping the Sonic Underground, he and his posse are given homes.
Mindy LaTour and Mr. LaTour
is Sonia's old friend and a rich fashionist
. Her voice (talking and singing) was done by Louise Vallance
, who also did the singing voice of Sonia
. Her father is very protective of her. He was forced to create robotic watches for Robotnik.
is a giant whale
mistaken for a sea monster. A parody of Moby-Dick
Oracle of Delphius
The Oracle of Delphius is a Mobian prophet, resembling a reptilian anteater. He is one of the resistance's most powerful allies, perfectly capable of withstanding an attack by numerous enemies. He serves to test Sonic, Sonia and Manic the Hedgehog as they struggle to end the war and find their mother. His name is likely derived from the Oracle of Delphi in Greek mythology.
Queen Aleena the Hedgehog
She is the mother of Sonic, Sonia and Manic. She is on the run so she has no freedom and she does what she can do for her children.
is an ancient queen who resembles Sonia. She is worshiped by penguins
is a desert dweller who lives in the city of Tashistan with his mother, father and grandmother. His best friend, Sonia
, momentarily loses her memory. He is Roboticized in the legs (like Bunnie Rabbot
is the leader of the Resistance in Anez. She appears in the episode Sonia's Choice
Sonia the Hedgehog
Sonia is the sister of Sonic the Hedgehog and Manic the Hedgehog. She is the middle age of the three children, and the most responsible and levelheaded. She takes a lot after her mother, though her fur is far more of a reddish shade. Her 'hair' is a purplish-pink color. Unlike her brothers Sonic and Manic she was raised by a wealthy family and, as a result, has a somewhat snooty demeanor. Despite being a fugitive, she still takes pleasure in many things that could be called luxuries (facials, spas, etc). Her weapon is a keyboard, which is capable of shooting lasers. She appears to have a crush on Knuckles the Echidna
A wolf with purple body armor and blue cape, Sleet is cunning, greedy and manipulative. He was once an independent contractor partnered with the idiotic Dingo, but Robotnik 'persuaded' them to work exclusively for him. His task is to hunt down the Sonic Underground band, Queen Aleena, and other Freedom Fighters.
Because of Dingo's incompetence, Sleet often makes him into a scapegoat, and never hesitates to use the strange remote that transforms Dingo into other objects. Despite countless failures, Sleet does on occasion have a successful plan up his sleeve. Sometimes he and Dingo think of plans that make them turn on Robotnik, but these never go well. Sleet's voice was done by Maurice LaMarche.
is a Roboticized chimera
-like robot made up of some of the fastest creatures on Mobius. It is used by Robotnik in a race to capture Sonic but instead ended up racing Dingo who ramed it into the wall of the track, it then bounced of it and went flying right on top of Bartleby.
is a tiger
who lives in Lake Valley. He has a crush on Sonia
, but originally was a spy for Robotnik only to protect her. After Robotnik betrayed him, and tried to destroy the resort, Stripes was almost Roboticized, but was rescued by Sonia. He then joined the Resistance.
was a professional conman, pretending to be a scientist who has developed a De-Roboticizer that can also immunise people against roboticisation. He would target the aristocracy and other rich people, conning them into paying for immunisation. He was coerced by Robotnik into turning his fake into a real Roboticizer as a trap; suffering an attack of conscience, he pushed Sonia out of it at the last moment as roboticized himself as a result.
is a mouse
who is a friend of the royal siblings and Cyrus
. He dresses like a hippy
. He is an ace pilot and helps build and fix mechanical equipment. However, he can be easily captured and has been close to be under the effects of roboticization before. He has appeared in several episodes to help the hedgehogs during some of the missions.
is a black-market salesman. Manic sells an orb to him before realizing it is a bomb, but by the time they get there, Vince has sold it to Bartleby
. Vince ends up getting Roboticized by Sleet