Franchise: Sonic The Hedgehog

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

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.

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.

Despite being synonymous with the "edgy" 2000s era of the Sonic franchise that Sonic Frontiers hearkens back to, Shadow the Hedgehog is completely absent from the game. No official comment has been expressed on why Shadow is omitted, however, a month before Frontiers' launch, the game's writer Ian Flynn would quote retweet a screenshot of an interview with writers for the Sonic Boom cartoon claiming that Sega are restrictive on Shadow's portrayal to the point where it's preferable to omit him in spite of his fan-favorite status than work with Sega's restrictions, with the caption "[quote-retweeted] without comment".

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.

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.

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.

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.

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.

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.

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.

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.

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 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.

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.

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".

Dr. Starline the Platypus from the IDW Sonic the Hedgehog comic series is inspired by a glitch character from Knuckles' Chaotix - a silver, red and charcoal Knuckles recolor, known by fans as "Wechnia", but by the game itself as "**********", seemingly based on unused data for Tails. Starline's color scheme is taken directly from Wechnia, his name is a literal take on the name "**********", (or "star-line") the black streak in his fur resembles the red streaks all over Wechnia's fur, and the choice of a platypus seems to be inspired by how certain Wechnia sprites would make the bottom of his muzzle yellow and loosely resemble shading for the underside of a flat bill, alongside platypi being Australian like echidnas.

During the reboot of Archie's Sonic the Hedgehog comics, several characters and aspects adapted into the comic from the 1993 Sonic the Hedgehog cartoon (commonly referred to as "Sonic SatAM") were noticeably altered for a variety of factors:

• Ixis Naugus (referred to simply as Naugus in the show) was changed to "Walter Naugus". His species (which was never actually stated in the show, though the pre-reboot comics depicted him as a rhino-bat-lobster hybrid) was changed to that of a troll, with a tail being added to his design to help make him look as such, alongside his attire being updated to more resemble a warlock. Additionally, despite what was initially believed, the term "Ixis" was originally applied to Naugus' cartoon production materials, and was not invented by former writer Ken Penders. This meant it was still usable in the comics, and was later given to the deity worshipped by the troll species.
• Muttski was changed to "Ben "Mutt" Muttski", and was changed from a non-anthropomorphic dog to an anthropomorphic one. Notably, his new name was given in honor of Ben Hurst, the main writer of "Sonic SatAM" who sadly passed away in 2010.
• Snively Robotnik (referred to simply as Snively in the show) was changed to "Doctor Julian Snively", with his first name being a nod to "Sonic SatAM", as Dr. Robotnik's original name in the show was Julian. According to Ian Flynn, he is no longer related to Dr. Eggman in the reboot due to Sega's mandates not allowing other media to invent family members for the main "SegaSonic" cast. Ironically, while his half-sister Hope Kintobor was removed from the reboot, Snively inherited her position as G.U.N.'s R&D Specialist.
• Maximillian Acorn (referred to simply as "The King" in the show) was changed to "King Nigel Acorn". His name was most likely changed due to being coined by former writer Ken Penders. Notably, his new name, speech pattern and mannerisms are shared with Nigel Thornberry from the animated series "The Wild Thornberrys": Nigel was voiced by British actor Tim Curry, who also voiced the King in "Sonic SatAM".
• Nicole the Holo-Lynx's new backstory in the reboot has her being created by Dr. Ellidy in an attempt to digitize the consciousness of his dying daughter Nikki. This may have been loosely inspired by Ben Hurst's plans for the cancelled third season of "Sonic SatAM", where it would have been revealed that Nicole was originally a normal girl until she was tricked by Dr. Robotnik into having her entire personality transferred into a computer satellite.
• Although the Wolf Pack originated from "Sonic SatAM", the only member of the group who was not created by Ken Penders was their leader Lupe the Wolf, who also originated from the show. As such, when the comic was rebooted, she was the only member of the group to be carried over.
• Aside from King Acorn, the only parent of a "Sonic SatAM" character to make it into the reboot was Sabina, the mother of Dulcy the Dragon and herself a character from the show. However, while Ian Flynn did confirm that she was still Dulcy's mother in the reboot, she never actually appeared in the comic prior to its cancellation. Additionally, given that Dulcy refers to her with present tense, it's likely that Sabina is still alive in the reboot, whereas she had died in the original continuity.

In the 41st issue of the IDW Sonic the Hedgehog comic book, Sonic taunts Dr. Eggman with the nickname "Baldy McNosehair," to which Eggman responds with "That's not funny! It's never been funny! It's never going to be funny!" This is a reference to the YouTube channel TeamFourStar and their web-series "Dragon Ball Z Abridged". Specifically, it references the video "DragonBall Z KAI Abridged Parody: Episode 2" in which Krillin dubs himself, Gohan, and Vegeta as "Team Three Star", and Vegeta yells the same response.

In 2022, Logan McPherson, the director of the animated series "Sonic Prime", stated that the show was canon to the games, drawing upon their existing mythology. This would make Sonic Prime the first television series based on the Sonic franchise to be considered canon to the mainline series. Ian Flynn would further support this claim, revealing that he knew when exactly in the series timeline the show took place in, but would not reveal it until after the show ends, while noting that something happens in the show to make it clear that it is indeed canon to the games. In 2024, after the release of Sonic Prime's third and final season, Ian Flynn finally confirmed the show's status in the overall Sonic timeline: aside from taking place sometime after the events of Sonic Advance 3, the show's placement is considered moot due to the ending Spoiler:having the show wipe itself out. In response to complaints regarding this outcome, Flynn claimed that its placement in the canon was intentionally vague, and the show being canon to the games at all was not his decision due to only being involved in the animated series as a consultant. He later claimed that he and other parties had made efforts to flag the show's inconsistencies early on in production, but that many of these efforts were flat out ignored. He noted that there was not an easy way to brush these issues aside, but also made a point that there was an effort to do so.