Franchise: Sonic The Hedgehog

In 2017, the official Sonic the Hedgehog Twitter account posted a parody of Marvel vs. Capcom: Infinite's character select screen, with various characters from throughout the Sonic franchise in place of the game's playable roster. This was likely meant to poke fun at Infinite's roster, which many had described as "mediocre".

In Issue #48 of the IDW Sonic the Hedgehog comic series, pages four and five depict several Central City citizens with designs that reference characters from other franchises, such as:

• Wally from Where's Wally?
• Reigen from Mob Psycho 100
• Conan and Ran from Case Closed
• Wreck-It Ralph and Vanellope von Schweetz from Wreck-It Ralph
• Crinkly Wrinkly from OK K.O.! Let's Be Heroes

Incidentally, the Sonic series has crossed over with both Wreck-It Ralph and OK K.O.! Let's Be Heroes in the past.

The character of "Ugly Sonic" in the 2022 film Chip 'n Dale: Rescue Rangers is based on the infamous first design of Sonic the Hedgehog featured in the first trailer for his 2020 film. Voiced by Tim Robinson, Ugly Sonic acknowledges the mockery of appearance (especially his realistic humanoid teeth) and uses it to find new work.

According to the director Akiva Schaffer, the company that provided the effects for this film, MovingPictureCompany, also provided the CGI for the 2020 Sonic film, meaning for Ugly Sonic, they had to "repeat their mistakes on purpose this time."

Interestingly, Ugly Sonic wasn't originally planned to be in this cameo; Jar Jar Binks from Star Wars was initially meant to be featured as the character acknowledging his mockery.

Some of the names of the Arcade Shop missions in Lost Judgment which are unlocked through playing Sonic the Fighters are references to aspects of the Sonic franchise.

The missions for beating Sonic, Tails, Knuckles and Amy are all named after their themes from Sonic Adventure or Sonic Adventure 2: Live and Learn, Believe In Myself, Fighting Freak and My Sweet Passion.

The mission for beating Fang the Sniper is titled Knack For Trouble which could be a reference to both Fang's original Western name Nack the Weasel as well as his debut game Sonic the Hedgehog: Triple Trouble.

The mission for beating Bean the Dynamite is titled Mean Bean Machine after the 1993 Sonic-themed Western localization of Puyo Puyo, Dr. Robotnik's Mean Bean Machine. Ironically, Puyo Puyo did not appear in Lost Judgment despite being in it's predecessor, Judgment.

Finally, the mission for beating Espio is titled Chameleon Detective after Espio's role as a detective starting with Sonic Heroes. It could also be a nod to the Lost Judgment's protagonist Yagami being a detective who often needs to don disguises to blend into places.

The live-action Sonic the Hedgehog movie was originally slated to be released sometime in November 2019, but was delayed to February 14th, 2020 as a result of the reception to the film's debut trailer released on April 30th, 2019. The main cause of the backlash being that the film was planned to feature a humanoid redesign of Sonic that was so negatively received by fans and audiences alike that the film's team hired artist Tyson Hesse, who had previous experience with the Sonic franchise, to make a more visually appealing redesign for the final movie that was more positively received and incorporated into all previously-released film footage.

In an interview, Naoto Oshima was asked if the blue birds were a direct reference to the game Flicky. Oshima said yes, and also mentioned that he asked game's designer Yoji Ishii's permission to use Flickies in his work.

In 2012, Ken Balough announced that Big the Cat would be retired from the franchise for the time being as they could not find a good use for the character, and all things that they already tried didn't work out for him. This however did not stop Big from making cameo appearances in Sonic & All-Stars Racing Transformed, having a trophy in the 3DS version of Super Smash Bros. 4, having a spirit in Super Smash Bros. Ultimate, being playable in the mobile games Sonic Runners and Sonic Forces: Speed Battle, and even making a full appearance in Lego Dimensions and Team Sonic Racing. Big was eventually reintroduced to the mainline Sonic games in Sonic Frontiers.

There was almost going to be a Sonic game based on skateboarding made for the Xbox, GameCube, and PlayStation 2 called Sonic Extreme (not to be confused with the cancelled Sega Saturn game of the same name). This game was developed by a San Diego company called Vision Scape Interactive.

Development began in 2003 shortly after Vision Scape finished up Bare Knuckled Grind. The game was initially planned to be ported to other consoles. There were also going to other skateboarding games using the same engine, but with different intellectual properties, including the Nickelodeon TV show Rocket Power. Unfortunately, budget issues is what resulted in all 13 projects cancelled. They later worked on cutscene animations for Sonic Heroes, and later pitched to Sega the Sonic Extreme prototype.

The prototype was finished in a week, and originally had planned to use hoverboards. The player would be to race against Sonic or Shadow. Yuji Naka, former head of SEGA, was impressed at the time and asked Vision Scape to make design documents for the game. However, when they did show the documents to SEGA, they went silent.

Later on, in September 2005, Sonic Riders was announced. People at Vision Scape believed that SEGA took some of the concept from Sonic Extreme. and used it for Sonic Runners. However, legal issues from SEGA forced Vision Scape to shut down in 2006.

As a result of a sponsorship deal between the motor racing circuit Donington Park in Leicestershire, England and SEGA, the 1993 European Grand Prix was adorned with SEGA logos. Even the race itself was renamed the SEGA European Grand Prix.

Ayrton Senna won the rain-drenched event after passing four cars on the first lap and holding off his teammate Alain Prost through the race's length, and was presented a trophy which featured Sonic the Hedgehog. While the image of Senna holding this trophy was widely circulated around the Internet, it was unfortunately only a fake trophy used for a photo op. It's unknown what became of the Sonic trophy.

At E3 2004, SEGA displayed a tech demo of Sonic the Hedgehog for the Nintendo DS simply named 'Sonic DS'. The game played by swiping back and forth on the bottom touch screen to allow Sonic to gain speed.

Silver the Hedgehog was originally going to be an orange mink named Venice, but the developers decided against it and changed him into a hedgehog as they didn't think that a mink would fit in with the other characters.

Tomoya Ohtani, a recurring composer for the series, frequently samples a portion of the famous drum break from the song Amen, Brother by The Winstons. This portion can be heard in 'Vs. Orcan' and 'Skullian' from Sonic Colors, the extra boss theme 'Boss - Big Swell' from Sonic Rush Adventure, and 'Cool Edge Day' from Sonic Unleashed, just to name a few.

Since Sonic was very popular in English speaking countries, one of Sonic's quirks in Japan (performed by Junichi Kanemaru) is that he may speak English at times, unlike other characters.

Andrew Rannells, the award-winning actor who played the lead character Elder Price in the play The Book of Mormon, was the voice director for the English dub of Sonic X. He played characters such as Bokkun, Decoe, Gamma, and Mr. Stewart. He also played the G.U.N. agents in the game Shadow The Hedgehog. Rannells actually worked on quite a few 4Kids shows during his time there, including Pokémon, Pokémon Chronicles, Kirby: Right Back At Ya!, F-Zero GP Legend, and voiced characters in 4Kids-acted games in the Yu-Gi-Oh and One Piece series.

The US Sonic Heroes manual states that Doctor Eggman is a feminist. This was added during localization and did not appear in the Japanese manual.

Sticks the Badger from the Sonic Boom sub-series resembles Aika from Skies of Arcadia, another Sega game. Both Sticks and Aika use a boomerang as their weapon of choice, have nearly identical hairstyles and have orange as one of the predominant colors in their design.

Fang the Sniper, called Nack the Weasel in the English release of Sonic Triple Trouble and various English-language comic books, originally wielded a realistic gun. However, this was considered too violent for the Sonic series, and was changed to a cork-shooting popgun during development of his debut game, Sonic Triple Trouble.

The skid noise made when Sonic stops running comes from Out Run, an earlier SEGA game.

Dr. Robotnik was created to be the opposite of Sonic, and to be the bad guy. During the development of the game, there was a growing debate between developers and environmentalists, and Robotnik was created to represent machinery and development, as apposed to Sonic, who represented the environment.

His egg shaped redesign came from Naoto Ōshima wanting to give the characters designs that were easy enough for kids to draw.

The English script for Sonic Colors, as well as other 3D Sonic localizations up to Sonic Forces, was partially written by Ken Pontac, known for working on children's programming such as LazyTown, Arthur, and Bump in the Night (the latter of which he co-created), and Warran Gaff, best known for his and Pontac's work together on the adult cartoon Happy Tree Friends. Pontac and Graff's renditions of Sonic were significantly more lighthearted than earlier or later 3D games, a highly requested shift at the time that would prove controversial after a few games - this disdain for Pontac and Graff's writing style lead Pontac to decline from doing Sonic panels at conventions out of fears that vitriolic Sonic fans will visit and harass him.