Sonic the Fighters is a special game for a number of reasons, and one of those is that it introduced the world to Bark the Polar Bear. The fighting polar bear (which would be a great name for a college sports team) only had one non-cameo appearance in a Sonic game, but he's also in Fighters Megamix. While Bark might not be a prominent character, he makes up for it by being a polar bear that wears a beanie.
While this list isn't ranked, you can rest assured knowing that Big the Cat would've been number one on the list. This lovable feline had his own storyline in Sonic Adventure which involved a lot of fishing (and a frog named Froggy who was #11 on my list). For some unknown reason, plenty of trolls on the internet like to act like Big isn't the best character, but we all know deep down who is the crème de la crème.
Yes, there was a Nack that captured gamers' hearts before Mark Cerny's dancing robot. The gun carrying character first appeared in Sonic the Hedgehog Triple Trouble, and has been relegated to spin-offs ever since (I assume SEGA doesn't want to make Shadow seem less edgy in comparison). Nack is best known for his appearance in Sonic the Fighters (as Fang the Sniper, which is a pretty darn cool pseudonym).
Dr. Robotnik is a great character, and even has a mean bean machine that's more fun than most Sonic games. Despite SEGA's best attempts to retcon the mustachioed villain's name to be Doctor Eggman, true fans will know his name is Robotnik. Long live Robotnik, the savior of Mobius.
Another Sonic the Fighters alumni, Bean the Dynamite is a bomb aficionado despite what his name implies. He's also a hidden character in Virtua Striker 2, SEGA's soccer franchise, so he's a pretty talented duck.
Not only has Dr. Robotnik created fantastic puzzle games (even if they're just a reskin of Puyo Puyo), he's also designed a robotic version of Sonic. Named Metal Sonic (apparently the soi-disant Doctor never took a creative writing class), the robot has been the primary antagonist in several games. His skills may be comparable to his rival, but Metal Sonic gets the edge by never having been voiced by Urkel.
You either die a Hedgehog, or you live long enough to see yourself become the Werehog.
I know. You're wondering how Knuckles somehow made it on this list. After all, the red echidna was universally hated for well over a decade. Thankfully, SEGA recognized this, and turned Knuckles into an athletic tape wearing, Drostanolone injecting cool guy. So while Sonic Boom isn't a good game, it at least brought the new (and very much improved) Knuckles into our lives.
Okay, so it appears that Dr. Robotnik might have a tad obsession with Sonic and his friends. I could understand making a robotic hedgehog (after all, they're really cute animals), but why would someone create a creepy looking doll that looks like Miles Prower? The stuffed animal (which is far scarier than Chucky, and has probably claimed 10x the casualties) originally appeared in Sonic R, and hasn't really been in a game since. SEGA probably doesn't want to give kids nightmares, but I do, hence Tails Doll is on the list.
The leader of the Chaotix Detective Agency, Vector has been a well liked character ever since his debut in Knuckles Chaotix. This is probably due to the crocodile looking like he's straight out of a 90s FUBU advertisement. Vector is a regular in spin-off titles, and has the positive trait of not being Chip from Sonic Unleashed.