Sonic the Hedgehog 4: Episode I (ソニック・ザ・ヘッジホッグ4 エピソードI Sonikku za Hejjihoggu 4: Episōdo I?) is a video game in the Sonic the Hedgehog series. It is the first episode of the Sonic the Hedgehog 4 episodic video game series. This episode was released in October 2010; it was originally to be released in the summer of 2010 but was pushed back for further development. The game was first announced on 8 September 2009, and its real name was revealed on 4 February 2010.
The game is a 2.5D side-scrolling platformer reminiscent of the original Sonic games, with an emphasis on speed. It is playable in high definition. For Episode I, the iOS version was released on 8 October, the WiiWare version was released on October 11, the PlayStation Network version was released 12 October and the Xbox Live Arcade version was released 13 October. On 19 January 2012, Sonic 4 was released for the PC on Steam. A direct-follow up, Sonic the Hedgehog 4: Episode II, was released on 2012. As a continuation of the Sega Mega Drive Sonic games, it features a simple control scheme, no voice acting, level design emphasizing platforming and momentum-based gameplay, and no player characters besides Sonic himself; however, it incorporates Sonic's design and abilities from later games like Sonic Adventure.
Some time after the Angel Island incident, with the Death Egg finally destroyed and the Master Emerald safe, Sonic parts with Tails and Knuckles to explore new territories on his own. Meanwhile, a vengeful Dr. Eggman has taken new measures to defeat his arch-nemesis by enhancing his past creations and mechs.
Despite Dr. Eggman's best efforts however, Sonic destroys each of his refined creations and chases the madman to Splash Hill Zone, where Eggman makes his departure into space. Using a rocket provided by Tails however, Sonic chases Eggman to his newest space station, the E.G.G. Station Zone. There, Sonic defeats each of the creations and traps that Eggman reuses against him, including a powered-up Death Egg Robot. At the end, after defeating the Death Egg Robot, Sonic triggers a chain reaction that destroys the E.G.G. Station. Making it safely back to his planet, Sonic celebrates his victory in Splash Hill Zone with his Animal friends. From there, the ending of the game will depend on the player's progress:
- If the player has not managed to collect the seven Chaos Emeralds, Sonic will be posing to the player in Splash Hill Zone. After the credits, Eggman will then be shown in the Egg Mobile laughing at the player, as the text "TRY AGAIN" appears below him.
- If the player has managed to collect all seven Chaos Emeralds and also collects all of the rings during the Splash Hill Zone sequence (by timing jumps perfectly as Sonic automatically runs) Sonic will use the Emeralds to turn into Super Sonic and pose to the player. If any of the rings are missed, the standard pre-credits pose without Super Sonic occurs. Regardless of which pose was triggered, after the credits, Sonic will then be making his classic pose before running to the right. Afterward, Eggman will appear in the Egg Mobile, laughing at the player before leaving the screen as well. Following that, a silhouette of Metal Sonic will be shown.
|Sonic the Hedgehog||Our legendary hero returns! With the Death Egg finally destroyed and the Angel Island back into the sky, Sonic decides it's time to take a break and heads off to find a new territory of his own. However, unbeknownst to Sonic, Eggman has also survived their last encounter, and has begun to taking measures to get rid of our hero. Armed with his Signature Speed, super Spin Dash - and powerful Homing Attack, Sonic is ready for an all-new adventure!|
|Dr. Eggman||After losing the Master Emerald during his last encounter with Sonic, Eggman regroups with a new objective; to revisit and refine the best of his creations in an effort to finally rid himself of Sonic!|
|Motobug||The very first Badnik that Sonic ever encountered, this metal beetle returns to try and take down Sonic one last time. Watch out - he will turn around to chase Sonic if he misses.|
|Newtron||Newtron surprises Sonic again using optical camouflage to try and blast Sonic. He can also transform into a rocket and charge towards Sonic.|
|Bubbles||Bubbles is a balloon fish type robot who returns back from the ruins of Angel Island. Due to Eggman's budget cuts, not all versions of Bubbles are spiked. However, watch out for the red ones!|
|Chopper||First seen jumping out at Sonic from under the bridges of Green Hill Zone, this deadly Piranha robot is back and still hungry!|
|Buzzer||Buzzer flies in from Emerald Hill Zone ready to blast Sonic with his stinger cannon.|
|Jaws||Specializing in underwater patrols, this lethal fish is on the lookout to put an end to Sonic's aquatic adventure.|
|Batbot||Batbot first appeared in Carnival Night Zone and returns in Sonic the Hedgehog 4. Be careful as Batbot chases after Sonic with his deadly lightbulb!|
|Burrobot||This Badnik prefers underground areas which are well suited for his unique talents. Be on the lookout as Burrobots have a habit of jumping out of the ground!|
|Orbinaut||The Orbinauts return as one of Sonic's most challenging Badnicks![sic] Pay close attention, you only have a split second to defeat them.|
|Shellcracker||Hailing originally from Metropolis Zone, Shellcracker has returned to make Sonic lose as many rings as possible, if not finish him off entirely. Watch out as this Badnik's main weapon is a quick-moving claw that packs a serious punch!|
|Slicer||Slicer - how could we ever forget you? The one Badnik everyone loves to hate. Slicer can fire off its arms at our blue hero, making it a formidable foe that will require a lot of practice to defeat unscathed. Timing is key, so don’t hesitate for a second if one of these robots spots you!|
Sonic the Hedgehog 4: Episode I is a 2D side-scrolling platforming video game, which features gameplay nearly identical to past 2D Sonic games. The game is divided into five Zones, each split into three Acts and a fourth, shorter Act featuring the boss of the Zone. The only playable character in the game is Sonic, who can run, jump, Spin Dash, and use the Homing Attack.
The main objective of Sonic the Hedgehog 4: Episode I is to lead Sonic to the end of the Acts in less than ten minutes. As with past games, these Acts are branched into various paths that offer the player different secrets to find. To finish each of the three first Acts in each Zone, the player has to touch the local Goal Plate in each Act. In the fourth Acts on the other hand, a Capsule must be opened after defeating the local boss.
In gameplay, Rings appear scattered throughout each Act. The number of Rings carried by the player is displayed in the top left corner of the HUD. As with past Sonic games, Rings serve as the playable character's main method of protection from damage; if the playable character takes damage while they carry at least one Ring, they will not lose a life, though they will lose all their Rings. Taking damage while not holding any Rings will cost the player a life. The player can also instantly lose a life if they drown underwater, get crushed, fall into a bottomless pit, or spend ten minutes in the same Act. After losing a life, the playable character will respawn at the latest Star Post they touched, or at the start of the Act if they have not touched any local Star Post. If the player runs out of lives, they will get a Game Over. Extra lives can be obtained by breaking One-Up Item Boxes, collecting one hundred Rings, or each time the player earns fifty thousand points.
The secondary objective of Sonic the Hedgehog 4: Episode I is to gather the seven Chaos Emeralds by completing Special Stages. To enter a Special Stage, the player must collect at least fifty Rings in any of the first two Act of a Round and then enter the Giant Ring at the end of them. Collecting all seven Chaos Emeralds will allow the player to turn into Super Sonic after obtaining fifty Rings.
|Wii||PlayStation 3||Xbox 360||iOS/Android|
|left/right||Left stick left/right||Movement button left/right||Move|
|up||Left stick up||Movement button up||Look up|
|down||Left stick down||Movement button down||Look down/Crouch|
|/||/||Jump button||Spin Jump/Shake Special Stage|
|in midair||/ in midair||/ in midair||Jump button in midair||Homing Attack|
|Move + down||Move + left stick down||Move + movement button down||Spin Attack|
|Crouch +||Crouch + /||Crouch + /||Crouch + jump button||Spin Dash|
|Tilt Remote||Tilt Sixaxis||Left stick||Tilt device/swipe screen||Rotate Special Stage|
- Air Bubble
- Chaos Emerald
- Giant Ring
- Item box
- Time Bonus
Gimmicks and obstacles
- Egg Mobile-H (Splash Hill Zone)
- Catch Eggman (Casino Street Zone)
- Egg Mobile (Lost Labyrinth Zone)
- Flying Eggman (Mad Gear Zone)
- Death Egg Robot (E.G.G. Station Zone)
Special Stages in Sonic the Hedgehog 4: Episode I are akin to the ones from the original Sonic the Hedgehog, where Sonic must navigate a maze to reach the Chaos Emerald, collecting Rings and avoiding the exit blocks. This time, the rotation is controlled by the player instead of automatically. Controllers with motion control support can use either a traditional control method or by tilting the controller to control the rotation.
Two significant differences between these stages and the original ones are the inclusion of ring gates and a time limit. Ring gates are barriers that prevent the player from crossing into the next area of the stage, but can be passed once the appropriate number of Rings, shown on the gate, have been collected. A time limit also kicks in at the start of each stage and boots the player out if they haven't collected the Emerald in the time frame. The starting amount varies by level (30 seconds for Stages 3 & 5 and 90 seconds for the others), but can be extended in five, ten or fifteen second increments by collecting orbs around the stage.
Once a Special Stage has been completed, it can be replayed on the level select stage in either Score or Time Attack modes, with a 1-Up replacing the Emerald. Once the player obtains all seven Chaos Emeralds, Sonic can transform into Super Sonic during a regular level except for boss fights.
The game was developed by Sonic Team as well as members of Dimps. The game was released as a digital download for WiiWare, PlayStation Store, Xbox Live Arcade and iPod app store services. Jun Senoue helped to compose the music of the game.
In an interview, Takashi Iizuka stated that "Fans [would] be very pleased with the cast in Episode [II]," implying that Sonic would not be the only playable character in future episodes. He also announced an as-yet unknown new move for Sonic, as well as that the Homing Attack would appear in the game, saying that he "wanted the user to enjoy an easy-to-play feeling by the attack sequence that this [Homing Attack] allows, and find the fun routes in the air." He also stated that the classic Special Stages will make a return and Ken Balough stated that there will be a total number of 17 stages in Episode I; including Special Stages.
The game would be nearly identical on all consoles, with the Wii and PlayStation 3 version of the game using motion control in certain areas such as Special Stages. The iOS version of the game would be featuring two of its own levels. Previously, the console versions of the game were going to have gimmicks such as Sonic riding on a Mine Cart, but Sega had delayed the game and moved the date from July 2010 to late 2010 because they wanted to change the game to make it better and to prevent fans from knowing all of the game due to the leaks the game was getting. The Mine Cart gimmick was later moved to the iOS version of the game, as well as some other gimmicks.
On 8 February, Sonic 4 brand manager Ken Balough went on record to confirm that work on the next installment was underway. Sega of America and Europe also provided feedback and input on the subject matter. Episode II was revealed to have its own original Zones as Episode I was a throwback to the original Sonic the Hedgehog and Sonic the Hedgehog 2.
The game was playable by the visitors of the Electronic Entertainment Expo (E3) 2010. Players were only able to do the whole level of Splash Hill Zone. The Special Stages of the game were not shown. The game was highly praised at the E3 and there was a lot of audience at show of Sonic 4.
Leaks, delay and fan-reaction
In February, a build of Episode I was submitted to Xbox Live Arcade's PartnerNET service, where developers were given access to upcoming downloadable titles for testing purposes. Soon after, screenshots, music and progressively more gameplay footage were leaked onto the internet. Eventually, a playthrough of the entire game was leaked and Sonic Retro, which had already banned leaked material when more than they approved of had been released, responded by banning Sonic 4 discussion for several days. As well as this, PartnerNET shut down for a night. Other websites also made efforts to crack down on leaks, such as banning posting of leaked content. The build was controversial, due to it containing "floaty" physics speculated to be due to its using the Sonic Rush engine, poor animations and criticized the level design features such as gimmick-based acts that were disliked by most fans.
On 20 May 2010, Sega announced that due to fan input, the game would be delayed until later in 2010, in order to extend the development of the game. They stated in game magazines and online that this was specifically done to allow various fan requests (since the game was leaked) to be implemented, including more momentum-based level designs and improved physics closer to that of the Sega Mega Drive titles.
Releases for iOS devices were also announced, finally ending speculation of the fourth unknown platform, although it was leaked months before when images were found in the website's source code. It was also revealed that the iOS version would receive two extra levels, which turned out to be the Mine Cart and Pinball gimmicks stages in Lost Labyrinth Zone Act 2 and Casino Street Zone Act 2, which were heavily criticized in the leaked gameplay footage. Sega said this was done because the levels fit the mobile controls more. Fans speculated that the console versions would receive new, non-gimmick levels to replace them. Sega confirmed this with pictures several weeks before the final release. The new, console-specific levels were much closer in design to the other levels and featured new gimmicks which require platforming.
Sonic the Hedgehog 4 has been criticized due to the design and content of the game. Some people believe that it is not a true sequel to the classic games, due to Episode I's content being largely based on that of previous games with minor changes, and level design that features speed boosters in every level (a staple of Dimps' level design with their previous Sonic games) and object placement that forces the use of the Homing Attack. The latter is a move that some fans do not feel belongs in a 2D game, particularly not one based on the classics and set before its debut in Sonic Adventure. The music has also been criticized, due to it featuring low-quality synths and drum samples (the latter from Sonic the Hedgehog 2, not the more advanced ones from Sonic the Hedgehog 3) that vary little between songs.
A highly controversial item is Sonic's design, which is the modern style model that debuted in Sonic Adventure and has since received refinements until its most recent state in Sonic Unleashed. Many fans believe that the classic Sonic design should have been used and a petition was set up for Sega to include the different version. However, in a magazine, Takashi Iizuka said that the classic style wasn't returning, as all games since Sonic Adventure have featured Sonic in his modern design (excluding Sonic Generations for having both Sonics in the game).
The game was first announced through GameSpot by Sega of America on 8 September 2009, the eve of the 10th anniversary of the launch of the Dreamcast console and its launch game, Sonic Adventure,in North America. At the time, it was referred to as "Project Needlemouse," in reference to the name "Mr. Needlemouse," which was the mistranslated prototype code name of Sonic the Hedgehog when he was being pitched as a new mascot for Sega.
The initial announcement was accompanied by a brief teaser trailer, which included sound effects from Sega Mega Drive-era Sonic games, as well as an interview with Sega's associate brand manager, Ken Balough, who acknowledged that "old-school Sonic fans have long asked to see Sonic return to a more 2D style of gameplay", and that "Needlemouse is that critical first step that brings Sonic back to his 2D roots".
To get fans pumped for Project Needlemouse, Sega put together a week long trivia game on the blogs.sega.com web page. Each day until Friday they are going to put a rejected stamp on the characters that won't be in the game. On Friday, the full list of characters would be revealed if fan's could succeed in a challenge. No information was given on whether the characters in the picture were the only potential characters in the game, so other characters like Tails and Knuckles still had the possibility of being in the game. The following was listed on the Sega blog:
- The Details: Each name on the picture above is a potential playable character in Project Needlemouse. However, not all of them are going to make the cut – and each day this week until Friday, we're going to update this picture with a rejected stamp over those who will not actually be showing up!
- The Challenge: Answer our trivia questions about oldschool Sonic games! (Mega Drive era) We'll post trivia questions each day on a specific part of our SEGA/Sonic sites, and you all have to work together to figure out the right answers and post them there! Each day we'll challenge you guys to get a certain number of people to post the correct answers – and if you meet that challenge, we’ll remove more names from the picture in a new blog the following day!
- About Bonus Points: If you go above and beyond the expected results, the community will earn a bonus point for that day. Earn at least three bonus points and we’ll give you all something special this Friday!
- Day 1 (11 January 2010):
- In Sonic 1, how many rings were needed at the end of an act to enter a Special Stage?
- Answer: At least 50 Rings
- How many emeralds were in the original Sonic 1 for Genesis/Mega Drive?
- Answer: 6 Chaos Emeralds
- What colors were these Emeralds?
- Answer: 1. Red, 2. Yellow, 3. Green, 4. Blue, 5. Violet, and 6. White.
- In Sonic 1, how many rings were needed at the end of an act to enter a Special Stage?
- Day 2 (12 January 2010) (Characters rejected: Charmy and Chip):
- What was the general name for the robot enemies in the early Sonic games?
- Answer: Badniks
- 50 Rings is always nice, but 100 is even nicer – why so?
- Answer: An Extra Life
- In Sonic 2 for the Genesis/Mega Drive, how many lives was a "continue" worth?
- Answer: 3 Extra Lives
- What was the general name for the robot enemies in the early Sonic games?
- Day 3 (13 January 2010) (Characters rejected: Vector and Tikal):
- How many Acts were in each Zone of Sonic 1?
- Answer: 3 Acts (except Final Zone)
- What was the first game to feature Super Sonic?
- Answer: Sonic the Hedgehog 2
- The original Sonic the Hedgehog featured Special Stages with morphing backgrounds – can you name two of the animals seen in that background?
- Answer: Birds and Fishes (There were no more animals)
- How many Acts were in each Zone of Sonic 1?
- Day 4 (14 January 2010) (Characters rejected: Shade and Amy):
- If you lock Sonic 3 onto Sonic & Knuckles, what was the largest amount of Emeralds you could collect from the Special Stage?
- Answer: 14 Emeralds (7 Chaos Emeralds and 7 Super Emeralds)
- Yuji Naka is credited for much of Sonic's history, but who is the man that actually designed Sonic?
- Answer: Naoto Ohshima
- During his creation, what was the Japanese name originally given to Sonic?
- Answer: Mr. Needlemouse
- If you lock Sonic 3 onto Sonic & Knuckles, what was the largest amount of Emeralds you could collect from the Special Stage?
- Day 5 (15 January 2010) (Characters rejected: Shadow, Froggy, Big and "Sonic's new friend Mr. Needlemouse"):
Conclusion of contest
The fans "won" the bonus points contest and was awarded not only two extra characters that had been struck off the list, but also a piece of concept art developed for the game (which is very similar to the same Badnik in Sonic the Hedgehog 2). A member of the Sonic fan community also went through the raw data of the file and discovered that it was scanned to the computer late the previous spring. The conclusion of the contest indicated that Sonic would be the only playable character in this game. However, a recent issue of GameInformer revealed that there would be more playable characters returning for the second episode of the game.
Concept art challenge
On 27 January 2010, Sega updated their blog with a second (and final) challenge and another piece of concept art (Motobug, the first Badnik encountered in Sonic the Hedgehog). The challenge was in response to a fan-made illustration of another Badnik from Sonic the Hedgehog 2 (designed to resemble the official art), which apparently staff liked a lot. To this end, Sega stated that they wished to see more: the new challenge was for fans to submit over 100 pieces of their own art of classic Badniks (from Sonic the Hedgehog, Sonic the Hedgehog 2, Sonic the Hedgehog 3 and Sonic & Knuckles, and any other game from that era) to Sega by the following Monday, to show them which enemies they wished to feature in Project Needlemouse. Sega stated that if this number was met, on 4 February 2010 they revealed the game's real name, concept art from the first Zone, and a trailer.
In June 2011, Sega announced a contest to celebrate the Sonic series' 19th anniversary where people would create videos, with the winner going to Tokyo to see the finished version of Episode I. The voting system was intended to allow one vote per day, however, people found workarounds to allow multiple voting by clearing their browser's cookies and cache due to poor site coding. On 16 July, Sega suspended the voting. On 2 August, the winners were chosen by input of Sega staff and Sonic Team.
|Nintendo World Report||8/10 (Wii)|
|Official Nintendo Magazine||88% (Wii)|
Sonic the Hedgehog 4: Episode I received generally positive reviews, with criticism focusing on poor physics and lack of momentum compared to the classic Sega Mega Drive Sonic games.
IGN gave the first episode a score of 8.0 out of 10 and an Editor's Choice award, calling it "short but sweet and well worth downloading." GamesRadar gave the PS3 version a score of 9/10, calling it "deserving of the name, Sonic the Hedgehog 4." The iPhone version had 168 reviews and all of them had given the game 4 stars out of 5. AppTilt had given the iPhone version a 9/10. GameShard gave the game a 9/10. AppAdvice also gave it a 4/5, whereas TiPb gave the iPhone version a 5/5. Nintendo Power had recommended the game for those who wanted "classic" Sonic gameplay. In aggregate reviews, the title received 81, 74, 72 and 70 via Metacritic (on the Wii, PS3, Xbox 360 and iOS, respectively) while GameRankings gave the game scores of 73.23% (PS3), 74.85% (Xbox 360) and 75.42% (Wii).
- The Special Stage in this game is styled after the Special Stage from the original Sonic the Hedgehog. Here, however, the player controls the rotation of the stage itself rather than controlling Sonic.
- On the Sonic the Hedgehog 4 website, the Egg Mobile has longer wings. The same goes for the Chopper.
- Once Sonic gains enough speed, his running animation looks similar to his running animation in the earlier games.
- The Zones in this game are based on previous zones from the Genesis/Mega Drive games (e.g. Splash Hill Zone is based off Green Hill Zone). Episode II keeps this idea, though only for Sky Fortress Zone.
- In the Xbox 360 version of the game, the player can unlock a Sonic costume along with a Sonic head for the Xbox Avatar.
- In Splash Hill Zone Act 3, the level turns from day to sunset. This is one of few times that something like this has happened in a Sonic game.
- In a similar fashion to Sonic the Fighters, Sonic uses a rocket ship that Tails built to get to E.G.G. Station Zone. This is not seen in mobile versions.
- Super Sonic is playable freely like in Sonic the Hedgehog 2, Sonic the Hedgehog 3 & Knuckles, Sonic Colors and Sonic Generations.
- Likewise, Super Sonic can be activated by a press of a designated button.
- The green Newtron Badniks launch themselves like missiles in this game, something only the blue Newtrons did.
- The game was intended to be released in July 2010, but it got delayed after test versions for the major consoles were slowly leaked and the fans reacted negatively to certain gameplay aspects and level gimmicks. The release date was changed to October 2010. The iOS release is, for all intents and purposes, the original version, as it retains some of the major elements. Further mobile ports are made closer to this version.
- Casino Street Zone Act 2 was originally a diversion in which Sonic had to acquire 100,000 points in order to reach the goal (using the slot machine is encouraged and helps acquire points faster). This level was scrapped for home consoles since testers felt that it forced the fun, so it was replaced with a longer level involving item cards, Eggman cards, and cards as flipping platforms. The music was also redone to suit the new area.
- Likewise, the player originally had to control Sonic in a mine cart throughout Lost Labyrinth Zone Act 2. This level was scrapped for home consoles and replaced with a much longer level in which Sonic lights his way through darkness and dynamite using a touch. Although there are still mine cart sections, it is not the focus of the level.
- This is the second Sonic game to feature a mine cart section as a gimmick, the first being Sonic Rush Adventure.
- Interestingly, in the second trailer, in the 1992 section (Sonic the Hedgehog 2), prototype sprites were used when Sonic is running.
- The mobile versions have a different waiting animation - rather than Sonic getting annoying as usual, he instead starts tapping to an iPhone near his ear and even happily spins around in place.
- As of the Sega Forever update, which gave Sonic a new updated model, this animation is no longer present.
- Depending on the device's capabilities, Sonic's rendering in the mobile version may look similar to his Sonic Rush and Sonic Rush Adventure rendering. Also, this rendering lacks a mouth, eyelids and an index finger for Sonic's pose after completing a Boss Act, unlike the console and PC versions, which do.
- The Wii version's rendering includes a mouth and index finger but still lacks eyelids. Also, when Sonic looks up, his mouth doesn't open, but it does in the PC and other console versions.
- At the ending, Sonic goes back to Splash Hill Zone and then jumps to the screen, as in the first game. Unlike the original Sonic the Hedgehog, Sonic isn't seen using and scattering the Chaos Emeralds.
- If the player manages to get all the Rings in the ending, then Sonic will transform into Super Sonic before jumping to the screen.
- In this game, Super Sonic is able to breathe underwater. This is an ability taken from Hyper Sonic.
- Special Stages can be restarted from the beginning, leading to an infinite number of tries to get a Chaos Emerald as long as the timer does not expire or Sonic does not land in a goal area.
- In this game, Super Sonic cannot be played in Boss Acts. This is due to each Act having less than 50 Rings to collect.
- If the game is hacked so that Super Sonic is playable during boss fights, Super Sonic has his own unique victory pose, suggesting that Super Sonic was originally intended to be playable in boss fights.
- This is the only Sonic game where the player can exceed the limit of 99 lives, whereas the limit in this game is 999 lives.
- The Wii version of the game has slightly different music than other versions. The music had to be compressed because of WiiWare's small file size limit, whereas every other version uses proper audio files.
- Additionally, the Wii version has a profile system where the player can save their progress (up to six profiles can be created), unlike the other versions which do not; they follow the profile format that Sonic Generations and Sonic the Hedgehog 4: Episode II have.
- This is the first and only original Sonic the Hedgehog game to be released on the Wii.
- This game is available in all of Apple's touch screen devices except the new iPod Nano.
- The game's title card is a homage to the original Sonic the Hedgehog title card.
- The boss theme for this game is actually an unused theme for a Mega Drive Sonic 3D Blast prototype.
- The character description of Tails on the Sonic the Hedgehog 4: Episode II website states that Tails was secretly supporting Sonic from the sidelines during the game, explaining the rocket Sonic used to get to E.G.G. Station Zone in the console/PC versions.
- The Shield does not disappear when turning Super, when getting it as Super Sonic or grabbing an invincibility power-up like in other Sonic games.
- In spite of the fact Mecha Sonic is not in this series, he is mentioned in Eggman's profile in the Japanese Episode I website.
- Since this game is set before Sonic Adventure, this is the first chronological appearances of Sonic's modern design and the Homing Attack (although not the first game appearances for either).
- Strangely, while playing as Super Sonic, he does not earn an extra life for collecting 100 Rings.
- Additionally, all Invincibility monitors change into 1-Up monitors; however, this only applies to the console and PC versions.
- In the console and PC versions, Super Sonic always wins at the slots.
- In Time Attack mode, the Acts' lampposts are not present and all 1-Up monitors change into Super Ring monitors.
- The same thing happens in all the Acts of Sonic the Hedgehog 4: Episode II.
- This is the first game since Sonic the Hedgehog CD to have Sonic as the only playable character in the major console.
- The PS3 version of the game is compatible with the PlayStation 4's DualShock 4 controller, however, it must be connected using a Micro USB Cable as it cannot be connected wirelessly using Bluetooth.
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