Crux is a mysterious and cold-blooded kid. The reason she's like this, is because of what happened to Green Hill before New Yoke City was created. She not only lost her mother in this accident, but also her ears (her ears resemble hair buns), to prevent her from flying. She wears blackish like clothing. "Where's Cheese?" well, gone.
Also, unless you want to kiss your ass goodbye, say something about her mother or cheese, or her past in a mocking way.

Something fanmade

Rosemary Prower, also known as Mama Prower, Miss Prower and Miles' mom, is a kind and caring mother. She's the widow of Amadeus Prower, and the mother of Miles.

Presumably killed by TurboAcorn.Ogg (Sally; Sonic.exe in this Au), and skin has been used as a way to trick Miles.

Miles' mother. // Sonic.EXE Au 

Miles Prower, often being called Tails (due to a birth defect), is a timid, gentle, insecure and laid-back anthropomorphic fox. Due to being bullied because of his twin tails (birth defect) and his machinery, Tails rather isolates himself from the others.
His tails, ears and 3 hair are EXTREMELY messy from the bullying.
This is *my* take on how Tails was before meeting Sonic.
He can sometimes stand up by himself.

THIS IS A FANMADE THING LOL

The Metal Virus is an object that appears in the Sonic the Hedgehog comic series and its spin-offs published by IDW Publishing. It was a synthetically concocted virus created by Dr. Eggman that transmutes organic matter into metallic matter. Its purpose was to turn people into robotic slaves (formely known as Zombot) in Eggman's army.

OG version.

Kade Crimson is a energetic and polite anthromorphic echidna. Usually kind, but if threatened, he can turn into a hotheaded grump.

He has a hammer especially made of crystals, though he uses it to only scare enemies and defend himself.

Sonic.EXE Au character.

The Kaleidoscope/Prismatic Factory is a corrupt, reserved and extremely strict factory owned by Canvas The Cat, right after betraying Eggman.
Inspired on Rainbow Factory (MLP Creepypasta made by Aurora Dawn), instead of the already colorless mobians being incinerated, they rather roam around the facility aimlessly (you can tell they're soulless because of their greyish colors; example, Tails is a greyish yellow, but his blue eyes remain).

"Every tinge of color is necessary, Doc." - Canvas

Bubble Wisp is a generically shy, nervous, anxious and yet confident Wisp (species from Sonic) who has the ability to use bubbles as it's main defense. It has 3 little pointy fingerless hands.
Whenever stressed or threatened, it cover it's face and lets out bubbles from it's head which harms anyone nearby's eyes.
Pinkish white skin, orange eyes.
Can only speak if it speaks through Miles Electric or Whisper (The Wolf)'s mask.
Wispon info below.

Fanmade wisp N1

Molar is a short-tempered, often hothead and strong yet gullible anthropomorphic tasmanian devil. He uses his childhood name "molar", due to the fact he has a very strong bite. When Molar snaps out, almost nothing can stop him; he'll bite through even steel.

A treasure hunter with a big bite.

Knuckles.ZIP The Echidna, or simply Knuckles.ZIP, is a demonic presence controlling the body of Knuckles The Echidna. Differentiating his personality from other demons, Knuckles.ZIP is usually cold-blooded, quick-witted and stoic, with a few traits of the original Knuckles such as his stubbornness and strong willingness. He also tends to feel "pity" for his victims when killing/torturing them, when in fact he's just being sadistic (however he can rarely feel empathy).

Cold-blooded, stoic, uses Knuckles as a vessel.

Practically a snowy version of Green Hill.

Breeze Knuckles has a backpack with a Paradox Prism shard inside it.

Some fan made thing ig 👍

Miles Prower is a sweet, polite and caring anthromorphic red (orange-ish yellow) fox. He is very naive and innocent, but has a big heart for everyone.
Indeed adorable.
As expected, he can fly with his two tails. Because of his sweet and caring nature, he never got bullied because of his two tails.

Mf when Sonic.EXE AU

Micheal Lifture, simply known as Dr. Lifture, is a scientist who not only studies science of course, but creates great machines like his og counterpart, Eggman.

This bot was before Micheal died.

He's Brazilian, and is married to Clair Robotnik.

Used to be a therapist.

Ryder and Grace's father, Deceased.

Haste, his actual name being Kade Crimson, is a free-spirited, adventurous, but often impatient and passionate anthropomorphic short-beaked echidna with red fur and white/green bandages on his quills (for pure style). 
He isn't as strong as the original Knuckles, but he's fast.
He rarely wears it, but he has his classic, stylish cowboy hat.
He does wear his boxing gloves, though they're there for pure cosmetic.
His fur is a brownish red, his eyes being green (which can change to blue or purple) 

Remade character from an old AU.

General Defer, often referred by his deadname Knuckles by Tempest, is a more short-tempered and aggressive version of himself, being mostly a soldier. As you could guess, this timeline of Knuckles works for the Thunder Empire. He wears metal (w/ shock ability) gloves.
He has a scar on his right eye, making him almost blind.
Short dreadlock quills.
If angered enough, his quills goes up, and his right eyelid opens, revealing his blind eye
never EVER deadname him, even if ur tryna get his attention

Knuckles, but something's off.

Cupcake is a NPC that can be found in-game and will enter the elevator. They are also able to hurt the player.
Cupcake looks like a anthropomorphic Pitbull, sporting a face similar to the default Roblox Face but instead a frown, having a navy gray color with white patches on her hands, muzzle and eyes. She also wears a metal muzzle and a blue sweater.
In her Christmas appearance, she wears a red sweater.
Personality: Quiet, short-tempered, reserved, laid-back, aloof, rarely talks.

She don't bite :3 // REGRETEVATOR OC 

Rocks is a sweet and polite, sometimes too naive, anthromorphic brown furred capybara, who currently lives at Rainforest Ruins. He wears long blue gloves, a necklace with a pin of a sunflower, and sandals with socks.
Due to his honest and caring nature, he has like, more friends than I do. Even Eggman.
Rocks is just too chill.
He can be a bit anxious sometimes.
Tries to comfort people when needed.

Transgender, He/Him and Bisexual.
Brazilian, and when he speaks English it's a bit janky.

OMG A CAPYBARA OGM

A Paint Wisp is a often energetic, hyperactive, happy-go-lucky and somewhat understanding Wisp (species from Sonic). It is one eyed, with two little round hands.
It cries ink.
It was made from a lab, which contrasts with the other Wisps.
Black "fur", with pink colored eye.
Can only speak through the Miles Electric or Whisper (The Wolf)'s mask, otherwise it will make squeaks.
Wispon info below.
Inspired on a vampire squid... I think.
It's color changes depends on it's emotions.

Fanmade Wisp N2

Hiro is a calm and well-mannered anthropomorphic brown cat with blue eyes, though sometimes a bit energetic with a hunger for adventure. Similar to Chris Thorndyke, he wears a black long-sleeved shirt with a light blue stripe on each side under a red t-shirt with white sleeves and yellow details, a belt hanging off the edge of his jeans with gray stripes, white socks, and blue and yellow stylish shoes with gray soles.
Has zero clue about who Sonic is, but he heard about him.

Or just mobian Chris Thorndyke, I guess

Horde Wisp, as the name suggests, is a yelpow with black patches Wisp (from Sonic). It is commonly seen in groups. Two purple half-closed eyes, no arms or legs. Three stingers which never come off.
Aggressive by nature, Horde Wisps can rarely be kind to other Wisps or Mobians.
Can only speak if it speaks through Miles Electric or Whisper (The Wolf)'s mask, otherwise it'll make buzz noises.
To make a Horde Wisp actually trust you, treat it politely and let it take it's time.

Fanmade Wisp N3

Cave Dweller Knuckles, simply known as ECHIDNA, is a quiet (like, very quiet), maniac and bloodthirsty parasite who has successfully (and unfortunately) found a host: Knuckles The Echidna.
It lives on caves, and uses the host's (still alive) corpse as a bait.
The rest of it's body is stuck to the ceiling, and it uses it's leg to connect itself on the back of the host.
Knuckles The Echidna has been missing since his birthday on February 2nd.
Attempt at a Analog Horror themed Sonic character.

"It followed me to Angel Island, Tails."

Ryder Lifture, simply known as Ryder, is a arrogant, happy-go-lucky yet stubborn and childish overlander/human. He's the brother of Grace Robotnik, and cousin of Maddie Lifture.
He has made a robot named Steam Tails, though he only finished the exoskeleton. His arrogance trait is a influence from Eggman. He also wields the Dupe Jasper.

Hates mobians with a burning passion

Clair is a egoist, yet kind and caring, but can sometimes get real angry, human.

She used to be from the Robotnik family, but now she's apart from the Lifture family, after marrying to Micheal Lifture.

The mother of two, as well as Eggman's sister-in-law.

She's not good at creating machines, but she's great at stealthiness and fighting.

Ryder's and Grace's mother, Deceased.

Kaz, her full name Kazuko, is a timid, polite and sweet anthropomorphic snow leopard, being the manager of her own Chao Garden, the Chao Mansion. She wears a blue hoodie, black pants and rain boots (not quite the style, but it's acceptable).
If threatened or touched, her fur "fluffs" up, making her fluffier than ever.
Social anxiety.
Due to being isolated from other mobians, she cares for the Chao she finds or gets requested to take care of rather than anyone else.

A Chao person.

Rumble is a quiet, short-tempered and laid-back anthromorphic indigenous anteater. She's one of the remaining members of the Anteater Tribe, which is a isolated place somewhere around Amazon Ruins. Much like Knuckles, Rumble is strong and independent yet gullible. She constantly carries a bag with a precious gemstone in it; the Master Quartz.

From the Anteater Tribe.

Gabs, their full name Gabriel Copperclaws, is a polite, caring and yet energetic and carefree anthropomorphic grey furred cabbit (cat + rabbit hybrid). Gabs almost always tries to see the good in people, regardless of who they are (except Eggman, Gabs is aware of how he is and knows their attempts won't work at all), keeping a optimistic and warm-hearted nature—otherwise, they're emotional, oversensitive and very much of a perfectionist.

Lovable little guy. Works at the Eggman Empire.

Eschew is a shy, laid-back, paranoid and yet optimistic anthropomorphic hedgehog. He is Bandit's sidekick and best friend, who always tells him to avoid danger, with Bandit doing it anyway. Eschew is around 3'4".

Bandit's loyal and soft sidekick.

Scuffle, or Nuzzle, is a NPC that can be found in-game and will enter the elevator.
Scuffle is a white-colored sphere with tiny legs and blue-colored shoes, a curvy smile and a single v-shaped nostril. It does not have eyes. It is also the species of a Nuzzle.
In it's Christmas appearance, Scuffle wears a scarf, a Santa hat and white shoes.
Although Scuffle cannot speak, it barks in a "silly" way, but the translation is exaggeratedly formal.
Personality: Friendly, congenial, touchy.

Weird dog thing // REGRETEVATOR OC

Movie Spiny, unlike her og counterpart, is a more reserved and laid-back, but still energetic and polite. She's a anthropomorphic sea urchin. She's not Sonic's "cousin" in the Movie version. She came from the deep seas, but was sooner trained by Agent Stone.
She carries a shotgun around, alongside some robots just in case.
Just like her "father", she makes coffees, cappuccinos, lattes, Etc.
NEVER. CALL ROBOTNIK "EGGMAN", OR SAY ANYTHING BAD ABOUT HER FATHERS. not in front of her.

Placeholder pfp since I don't have a computer

Canvas is a selfish, arrogant and narcissistic anthropomorphic black-footed-cat, who is a specialist in art (hence the name Canvas). His main weapon is a big brush, which he can use to create copies of mobians (named "Artlings"), control minds, barriers and many things that is related to ink.

He's no ordinary cat.

Almond, also known as Officer Mon and real name being Pepper, is a quiet, cold-blooded and caring anthromorphic mobian cat who worked as a police officer. Always wielding a taser, she is not a great fighter due to age, but is very wise and calculating.

A tired old hag /j

Plasma is a psychotic, selfless and devious anthropomorphic Honduran White Bat. Her main skills is healing and medical weaponry. She wears cyan latex gloves, short white scientist clothing, black pants + shoes, and light greyish cyan goggles. Her favorite food is parfaits, while favorite drink is cherry soda.
Trans male and pansexual.
Pacific villain.
Her eyes are spiral like, being yellow and magenta.
She's 3"2 (which goes to 4"3 if she put her wings up).
Schizophrenic :(
17 years old.

Eggman isn't going to like this one.

Grace Robotnik, also known as Grace Lifture, is a calm, quiet and laid-back (by that, she takes shit personally) human who currently works for the Eggman Empire. She's the biological sister of Ryder Lifture, and her personality contrasts greatly with him.

Hydrokinesis Master... number two.

Buster is a kind, polite and extrovert anthropomorphic maned wolf. He is able to stretch his tail and cause damage, which is something he tries to avoid. Although he has severe traumas, he usually tries to keep up a positive attitude.

Cinnamon roll <3

Hazel is a energetic, impatient, kind and extroverted mobian porcupine who lives at Amazon Ruins, Southern Mobius. She's not as fast as Sonic, but her spikes are perfect for battling.

From Hazel Venture, an upcoming(?) series

Mary Petals is a sweet, polite, optimistic and caring anthromorphic axis deer who currently lives at Blossom Meadows. She's the grandkid of Oswald Petals, and an orphan.

She wears clothing similar to Maria Robotnik's, minus the blue rings on her wrists.

She's a bit of the size of Eggman, except she's smaller. Taller than Knuckles, though.

She's 13.

She has no idea who Maria Robotnik is, neither anything related to her.

Or just Mobian Maria. Who knows?

Azure Shadow, also known as Metal Shadow, is a robotic replica of the Ultimate Lifeform itself. She (they didn't knew Shadow was a guy) may be weak, but she's really strong due to a fake phantom ruby being her main source of energy. Regardless of being outnumbered, she'll find her way out of battle. Cruel and cold-blooded as expected. 
Blue robotic pupils, black colored metal and scarlet pink stripes, as well as normal rings on her wrists.
CANNOT SPEAK!

Robotic replica of the Ultimate Lifeform.

Topaz is a loyal and determined soldier, though easily embarrassed and at times gives up too easily.
An anthropomorphic sandy brown furred puma with violet eyes, often seen wearing blue earrings and pink lipstick. In regard to clothing, Topaz is notable for wearing different attire more often than most characters. Usually, it is a smart dark blue or green government uniform with black low-heeled shoes or dark blue combat suit.

Or just Mobian Topaz from Sonic X, I guess.

Bandit is a snarky-for-good, outgoing, quick-witted yet impulsive anthropomorphic echidna. He's very adventurous and loves treasure hunting. He was apparently a lab experiment, designed after Knuckles' strength, although he doesn't know much of the world. Much like the red echidna we know, Bandit is 3' 7".

A lovable yet impulsive echidna!

Dazzle is a affable, energetic and quick-witted anthropomorphic ferret. She is able to twist and stretch her body, as well as fit through tight spaces. When she curls up into a ball and spin dashes (yeah, she can do this), she lets loose electric crackles and once she lets go, she often leaps forward and shock her surroundings.

Silly little critter.

Sha is my persona btw
ENFP
Can be a bit too silly sometimes, and can quickly change mood.
She is very, very innocent
Stupid to the point they're smart
Doesn't really give a fuck about dying since, well, they're the void
They/Them, Pansexual. Genderfluid, but they prefer being non-binary.

The literal void in the shape of a blob with limbs and tail (she's actually a gecko, except the muzzle)

Look its the silly goober

Mipp is a small (the size of a child) and chubby (enough to resemble a ball) version of Ray The Squirrel. It can somehow make Exes around (such as Xenophanes or hell even Lord X) it feel more chill and comfortable, even the ones who could possibly kill Mipp. Mipp legally cannot speak, only communicate through small chipmunk and squirrel noises.
If squeezed hard enough, it'll splat blood everywhere, but soon recover from it. It/They pronouns, Pansexual and Genderfluid.

Fluffy, stress ball looking.

Turbo Acorn, simply known as Turbo, is a independent, energetic and impatient anthromorphic chipmunk, who is Mobius' fastest being. She can act impulsive at times, due to anxiety.

Brawl is a fearless, often courageous, daring yet reckless anthropomorphic honey badger. Although impulsive and with a certain ego, surprisingly, she's able to team up with pretty much anyone because of how social she is.

Fearless, daring honey badger.

Violetta Syrup, simply known as Vio, is a sweet and polite, yet short-tempered and could become grumpy easily, who currently lives at Snowdin. She's known for being very careful about humans, and tries her best to avoid them (though it rarely works). Her powers are not known.

Bisexual, genderfluid.

A Undertale OC ig