|Sonic the Hedgehog 2|
Single player, multiplayer
Sonic the Hedgehog 2 (ソニック·ザ·ヘッジホッグ2 Sonikku za hejjihoggu 2?) is a platform game developed by Sonic Team in collaboration with Sega Technical Institute, and published by Sega for the Sega Mega Drive/Genesis. It was released in Japan on 21 November 1992 and in North America and Europe on 24 November 1992. It is the sequel to Sonic the Hedgehog and was directly followed by Sonic the Hedgehog 3 in 1994. The game formally introduces Miles "Tails" Prower as an addition to the cast and a new playable character.
The story follows Sonic the Hedgehog and Tails on their mission to stop the evil Doctor Robotnik from obtaining the Chaos Emeralds to power his Death Egg. Sonic and Tails must defeat Robotnik's army and free their friends.
Six months after its release it had sold around six million copies and became the best selling game on the Mega Drive. The game was compatible with Sonic & Knuckles' lock-on feature which allowed the player to play as Knuckles in Sonic the Hedgehog 2. It has been included in a number of compilations on a range of platforms. On 11 June 2007, the game was made available on the Wii's Virtual Console, and released for Xbox Live Arcade on 12 September 2007. On 27 April 2011, it had came to PlayStation Network.
Sonic the Hedgehog was looking for new adventures when he discovered West Side Island. Sonic landed his personal plane, the Tornado, on the island to check it out and relax, not paying attention to the fact that a certain metallic flying object was chasing him and suspiciously landed on the other side of the island.
It is said that a very long time ago, the people of West Side Island used a mysterious stone to advance their civilization and achieve prosperity. However, when those people tried to use the stone for the wrong reasons, their prosperity vanished overnight. It is believed that the kami sealed away the stone within the island's depths.
One day shortly afterward, Sonic noticed a shy orange fox tagging behind him, who nervously scurried back into the welcoming shade of the still palm trees when he was spotted. When Sonic was not looking, the peculiar fox barely managed to keep up with the blue hero. The fox's name was Miles Prower, though he was known as "Tails" due to his two special tails, which often made him the target of bullying. However, something changed in Tails when he saw Sonic come to the island, and he made up his mind that he wanted to be cool like Sonic. Realizing that the young kid was harmless, Sonic made friends with him and allowed him to hang around as he freely explored the island.
On an early afternoon, Tails discovered a lone aircraft stranded at the beach. Being a budding fan of machinery and vehicles, he rushed to take a closer inspection. He was admiring its magnificent build until he noticed that Sonic was taking a nap under its wing. Realizing that Sonic owned the plane, Tails gently retreated to the other side of it so as not to wake him. Suddenly, an ominous flash occurred in the direction of the nearby forest, followed by a terrific explosion. The wild fire blew away various debris, which Tails avoided by taking cover underneath the Tornado as he witnessed robots violently excavating the area. This ceaseless activity threatened to blanket the entire island in its destructive flames.
It turned out that Dr. Robotnik detected the presence of all Chaos Emeralds after following Sonic, including the lost seventh one spoken of in the island's legend. He took the opportunity to kidnap the island's Animals to rebuild his Badnik forces and finish his ultimate weapon, the Death Egg. Robotnik now ruled the factories, refineries and cities. He's grabbed control of everything except the seven Chaos Emeralds. The speedy hedgehog went off into the forest to set things right and the curious fox followed.
The heroic duo traveled through West Side Island, rescuing the kidnapped animals and stopping Robotnik's creations every time they face him. After liberating the island from Robotnik's control, the doctor took off to his flying fortress with Sonic and Tails following on his trail on the Tornado. However, the plane gets shot and Sonic has to continue on without Tails. After defeating Robotnik, the doctor retreats to the Death Egg but Tails returns with an upgraded Tornado allowing Sonic to catch up with the doctor. Onboard the space base, the two then have a climatic showdown with Sonic emerging victorious and the doctor defeated, causing the Death Egg to explode while Sonic escapes just in time falling through the Earth. He is then saved by Tails where the duo became best friends from the course of the adventure.
- Sonic the Hedgehog
- Miles "Tails" Prower
- Knuckles the Echidna (via lock-on and the 2013 mobile re-release)
- Chop Chop
- BBat (2013 re-release only)
- Redz (2013 re-release only)
- Stegway (2013 re-release only)
- Jellies (2013 re-release only)
- Snail (Debug Mode in 2013 re-release only)
- Bubbler's Mother (Debug Mode in 2013 re-release only)
The gameplay of Sonic the Hedgehog 2 builds upon the basic set-up of the original Sonic the Hedgehog game. The player finishes each level, generally moving from left to right, within a time limit of ten minutes. Along the way, Rings are collected and Badniks are defeated. Star posts serve as checkpoints, where if the player were to lose a life then he or she would return to one. When the player has collected at least 50 rings, star post will have sparkles on top that the player can jump into for an optional Special Stage. At the end of Act 2, Sonic confronts Dr. Robotnik, although there is an exception in the Metropolis level in which there are 3 stages.
Although zones have grown significantly in size since Sonic the Hedgehog, they now consist of two acts instead of three (with the exception of the Metropolis Zone, which has three acts, and the three final zones, which each have one), and there is greater emphasis on variety between levels. The gameplay has also become even faster; to that end, Sonic is able to perform a new special move referred to as the Spin Dash Attack. The Spin Dash attack allows Sonic to spin in place, as if revving up an engine, before taking off at high speeds from a stationary start. Sonic's running motion also features longer strides.
Special Stages track Sonic from behind while he runs through a (semi-) three-dimensional half-pipe course filled with rings and bombs. A certain amount of rings must be collected to pass through two checkpoints and then obtain the emerald itself. If the player runs into one of the many bombs (increasing in number as the emeralds are captured) he will lose a set amount of rings, varying depending on the stage. The order of stages is fixed in rising difficulty, and Sonic cannot enter the next stage without passing the previous (unlike Sonic 1). Whether the player is able to obtain the emerald or not, Sonic is transported back to the last star post he hit in the zone when the special stage is over and has zero rings.
From the options menu, players can select to either play as Sonic alone, Tails alone or Sonic and Tails. By default, players control Sonic while Tails tags along unhindered. However, a second player may control Tails separately. Should Tails move off-screen, falls off in the void, or dies after getting hit above, he will eventually return. There is minimal difference when playing as Tails instead of Sonic. Tails cannot fly when played as in this game, though he is several pixels smaller than Sonic, meaning he may not have to duck in some instances.
Sonic and Tails' abilities
|Name||Sonic sprite||Tails sprite||Description|
|Push left or right on the D-pad to initiate Sonic's/Tails' movement in either direction. As you hold the button down, Sonic gains speed.|
|Begin walking and hold down the button to make Sonic/Tails gain speed. After a few seconds, he'll break into a run.|
|While running, quickly press and hold the opposite direction on the D-pad to make Sonic/Tails screech to a halt. He'll skid for a short distance, based on how fast he was moving.|
|While standing still, press up on the D-pad to make Sonic/Tails gaze to the sky. Continue holding up for a few moments and the camera pans upward, giving you a view of Sonic's overhead surroundings.|
|While standing still, press down on the D-pad to make Sonic/Tails duck down. As you hold down, the camera pans downward, giving you a view of the stage beneath where Sonic/Tails stands.|
|While moving, press down on the D-pad to make Sonic/Tails curl into a rolling attack. He'll remain in this position until you jump or slow down. The speed of Sonic's/Tails' movement while in spin mode is based on how fast you're moving when you launch it, and also on the terrain Sonic/Tails rolls along.|
|Press , or at any time to make Sonic/Tails leap into the air with a spin attack. The height of the jump is proportional to how long you hold the button down.|
|Green springs in the Oil Ocean Zone can be pushed by running up against them. Continue holding the D-pad against the spring to have Sonic/Tails push it into the wall.|
|Super Spin Dash||While crouching, , or to have Sonic/Tails rev up with a stationary spin. Keep tapping the jump buttons to build up momentum, and let go of the D-pad to dash off with a full speed rolling attack.|
- Emerald Hill Zone
- Chemical Plant Zone
- Aquatic Ruin Zone
- Casino Night Zone
- Hill Top Zone
- Mystic Cave Zone
- Oil Ocean Zone
- Metropolis Zone
- Sky Chase Zone
- Wing Fortress Zone
- Death Egg Zone
- Hidden Palace Zone (2013 re-release and some betas only)
- Boss Attack Zone (2013 re-release, Time Attack only)
- Proto Palace Zone (2013 re-release, only accessible via Level Select)
Robotnik usually appears in his customized Egg Mobile at the end of each Zone's second Act, except in Metropolis Zone (which has three Acts), and Sky Chase Zone, Wing Fortress Zone and the Death Egg Zone (which have only one). Eight hits are required to defeat each boss, excluding the final boss (who takes 12 hits).
- Drill Eggman (Emerald Hill Zone)
- Water Eggman (Chemical Plant Zone)
- Tonkachi Eggman (Aquatic Ruin Zone)
- Catcher Eggman (Casino Night Zone)
- Submarine Eggman (Hill Top Zone)
- Drill Eggman II (Mystic Cave Zone)
- Submarine Eggman II (Oil Ocean Zone)
- Flying Eggman (Metropolis Zone)
- Barrier Eggman (Wing Fortress Zone)
- Mecha Sonic (Death Egg Zone)
- Death Egg Robot (Final Boss)
- Brass Eggman (Hidden Palace Zone (2013 re-release only))
Obtaining all seven Chaos Emeralds by clearing all of the special stages will unlock a new feature; Sonic's ability to change into Super Sonic. Sonic changes into his "Super Form" when he has collected at least 50 rings and jumps into the air. At this point, he glows yellow and is virtually invincible, although he can still die by drowning, getting crushed, falling off the screen, or running out of time. His speed, acceleration and jump height are all increased as well. This means that it is much more difficult to control Sonic in this form, especially when the player needs to make precise jumps. However, his Spin Dash Attack is decreased in effectiveness as the initial velocity is decreased rapidly. Super Sonic consumes one ring per second, and when he has no rings left or he reaches the end of the act, he reverts to his normal state.
If the game is played with Tails only and the player manages to collect all of the Chaos Emeralds, nothing happens.
2 Player VS
In two player versus mode, two players compete against each other -either as Sonic or Tails- in a split-screen race through three regular zones and one Special Stage. Regular zones include Emerald Hill, Casino Night and Mystic Cave and have different music from their one player counterparts, while the Special Stage remains the same as in single player. In the regular levels, players are ranked in five areas (score, time, rings held at the end of the level, total rings collected, and number of item boxes broken), with the player scoring highest in the most levels winning the round, while in the Special Stage, players compete to obtain the most rings. Once one player finishes one of the regular levels, the other player must finish the zone within 60 seconds or lose a life.
In case of a tie, an additional Special Stage round must be completed. Also, to heighten the stakes, there are two unique items in versus-mode: a Teleporter item that instantly switches positions between players in a zone, and a Robotnik item that damages the unlucky player. Furthermore, an optional setting allows that all item boxes in two-player mode are only Teleporters.
In Sonic the Hedgehog 2, there are 7 Special Stages. When Sonic has collected at least 50 rings and he hits a Star Post, a red halo of stars will briefly float above it, which Sonic can then jump through to get to a special stage.
Special Stages track Sonic from behind while he runs through a three-dimensional half-pipe course filled with rings and bombs. A set amount of rings must be collected to pass through three checkpoints and eventually obtain the emerald itself. Playing co-operatively with Tails (as seen in the screenshot) raised some of the ring targets in the early stages, for example in the beginning of the first stage 40 rings were required to pass rather than 30. The order of stages is fixed in rising difficulty, and Sonic cannot enter the next stage without passing the previous (unlike Sonic the Hedgehog). Whether the player is able to obtain the emerald or not, Sonic is transported back to the last lamp post he hit in the zone when the special stage is over and has zero rings.
On return from a Special Stage, the entire zone is reset (except the game timer) - the player is without rings but all the collected item boxes and rings reappear (although unfortunately so do the Badniks). Also, if Sonic activates a Star Post, all the Star Posts before that one will be activated as well, whether or not with 50 rings in hand. This created a tactical element to getting the most out of each zone in terms of opportunities to grab Emeralds. It is possible to collect all seven within Emerald Hill Zone, provided the player is careful with the order in which Star Posts are activated (and indeed, very skilled at the Special Stages).
While the original Sonic the Hedgehog was designed by Sonic Team in Japan, development duties for Sonic the Hedgehog 2 were handed over to Sega Technical Institute in the United States. However, experienced Japanese Sega members such as Yuji Naka and Hirokazu Yasuhara (the first game's lead programmer and game planner respectively) were brought in to work alongside the American developers.
A prototype of the game was discovered on a Chinese GeoCities site and has been widely distributed on the Internet. (This was widely known as the "Simon Wai prototype".) Only four levels can be played in "normal" gameplay; the rest (including several incomplete stages) have to be accessed through the level select code. Many are not entirely playable, but can be explored using Debug Mode. The prototype is frequently examined by hackers to determine how Sonic the Hedgehog 2 was developed. It was stated in an interview with Yuji Naka that this prototype was from a demonstration cartridge that was stolen at a toy show in New York in 1992. Akinori Nishiyama has also stated that the leak was due to the lack of security at the time.
There was also another prototype version shown on two episodes of Nick Arcade of a beta even earlier than the Simon Wai prototype, many stages in this beta had music from Sonic 1 instead of their usual music, such as Emerald Hill Zone playing Star Light Zone's music instead of its usual music, and Chemical Plant Zone plays Marble Zone's music instead of the music that plays in Chemical Plant Zone in the final, and the game has many elements from Sonic 1 such as the infamous spike bug (where if sonic hits one set of spikes, and flys into another set, he dies intermediately after hitting the spikes the 2nd time), and even Green Hill Zone even made an appearance, which was a very glitchy and unplayable version of Sonic 1's Green Hill Zone.
The game sold an overall of 6 million copies worldwide and is the best selling game for its respective console. Due to the popularity of its predecessor Sonic the Hedgehog, Sonic 2 already had an established fan base anticipating its release. The release of Sonic 2 was the main reason that Sega caught up to Nintendo in the "console wars". It brought their market share up to 50% within six months of its release. It went on to be the best selling game for the Mega Drive/Genesis, selling around six million copies altogether. It was well received by most gaming reviewers. It was praised for its large levels, colorful graphics and backgrounds, increased cast of characters and enemies alike, and music. GameSpot stated that "Time may have eroded Sega's prominence, but it hasn't done much to diminish how sweet Sonic the Hedgehog 2 is." and, along with other reviewers, commented on how it is still a fun game to play.
The game's main criticisms were of the two player mode that was a new introduction to the series. It suffered from slow down and some visual problems such as flickering and the small area for each player. It only offered four different zones that could be played with two players.
The game was released in Japan for the Sega Mega Drive on 20 November 1992. The Sega Genesis release in the United States and the European Mega Drive release came later on 24 November, a Tuesday and the release day was dubbed "Sonic 2's Day". Sega claims that they sold 400,000 copies of Sonic 2 in the first five days after release. It has since been re-released numerous times.
Sonic 2 with Sonic & Knuckles
Knuckles the Echidna in Sonic the Hedgehog 2 is a game activated by locking Sonic the Hedgehog 2 to the pass-through cartridge of Sonic & Knuckles that was released later by Sega. The resulting game is almost identical to Sonic the Hedgehog 2, except that the player plays as Knuckles the Echidna. As Knuckles has abilities and weaknesses that Sonic and Tails do not, the game is an overall different experience. Knuckles can glide in the air and climb walls with ease, which allows him to access areas otherwise unreachable by Sonic and Tails, while his weaker jumping abilities make some situations, such as certain boss fights (particularly the final boss of Death Egg Zone), more difficult.
|Sega Mega Drive (Genesis)||Included in Sonic Classics (Sonic Compilation in Europe) on the Sega Mega Drive (Genesis).|
|Arcade||This was one of the games adapted for release in arcades using MegaPlay and MegaTech technology in 1993.|
|Sega Saturn||Playable on the game Sonic Jam for the Sega Saturn console.|
|PC||Included in Sega Smash Pack 2 for the PC.|
|PC||Available in Sega Smash Pack 2 which is included in Sonic Action 4 Pack for the PC.|
|PlayStation 2 / PSP||Sega Genesis Collection for PlayStation 2 and PlayStation Portable also includes this game.|
|GameCube||Available on Sonic Mega Collection for the GameCube.|
|PlayStation 2 / PC / Xbox||Available on Sonic Mega Collection Plus for the PlayStation 2, PC and Xbox.|
|Xbox||Available in Sonic Mega Collection Plus / Super Monkey Ball Deluxe 2 in 1 combo pack for the Xbox|
|GameCube / PlayStation 2||Sonic Gems Collection allows you to play the final boss of this game in the museum mode. If you beat Death Egg Zone under the time limit, you can continue on to the beginning of the game until your time runs out.|
|Play TV Legends||Sega Mega Drive Collection Vol. 2 is a game console which is part of the Play TV Legends plug-and-play series. It has 6 built in games that can be played when the console is connected to the TV. The title game is Sonic the Hedgehog 2. This was released in Europe and Japan in 2005.|
|Play TV Legends||Included in Super Sonic Gold, a console that has 4 built in games, but no cartridge slot. Released in the US and Europe in 2005|
|Mobile Phone||In 2006 this game was ported as a mobile phone game and offered on the Sonic Cafe in Japan and Sega Mobile services elsewhere.|
|Mobile Phone||There are actually several different versions of the phone game. The game is split into 2 parts, titled Sonic 2 Dash and Sonic 2 Crash. Depending on the screen size, they are either identical to the Genesis original or lacking various elements (including Tails and bosses).|
|Wii||Available for Download on the Wii Virtual Console.|
|Xbox 360/Playstation 3||Available for Download on the Xbox 360's Xbox Live Arcade service and later made available for download on the PlayStation 3's Playstation Network service. Released 11 June 2007 for Xbox 360 and 19 April 2011 for PlayStation 3.|
|PlayStation 3 / Xbox 360||Included in a compilation disk titled Sonic's Ultimate Genesis Collection for the PlayStation 3 and Xbox 360.|
|PC||Sonic PC Collection is a compilation released in New Zealand and Australia in 2009. This compilation includes Sonic Mega Collection Plus which includes Sonic the Hedgehog 2.|
|Nintendo DS||Included on a Game Card titled Sonic Classic Collection for the Nintendo DS.|
|iPhone||Sonic the Hedgehog 2 was ported to iPhone on 20 April 2010. Like the initial port of the original Sonic the Hedgehog, this port removes the capability of inserting cheat codes.|
The 2013 re-release version by Christian Whitehead was available as an update to the earlier iPhone version and also available for Android devices. The revised version adds similar modernized touch-ups as Whitehead's previous works, adding exclusive features such as Knuckles as a playable character, a fully playable Hidden Palace Zone and a boss attack mode.
Mega Drive/Genesis original
- Display Tails' name as Miles: At the title screen press the following in order: Up, Up, Up, Down, Down, Down, Up. This can be done again to revert Miles' name back to Tails.
- Act select: - At the Options Sound Test, play the following tunes in order: 19, 65, 09 and 17 then press Start to return to the title screen. Once there press Start while holding to enter the Act select. During any Act, by pausing the game, press A to return to the Act Select.
- 14 Continues: At the Options Sound Test, play the following tunes in order: 01, 01, 02 and 04, then the select Player Select to start the game with 14 continues.
- Debug Mode: At the Act Select Sound Test, play the following tunes in order: 01, 09, 09, 02, 01, 01, 02 and 04 to unlock Debug mode. Then highlight any Act and press Start while holding .
- All 7 Chaos Emeralds: At the Act select Sound Test, play the following tunes in order: 04, 01, 02 and 06 in order to get all seven Chaos Emeralds.
- Level Select- At Game Start, select 'No Save Mode' and on the Sega screen, tap the letters S-E-G-A in that order, then hold two fingers on the screen untill the Level Select screen shows up.
- Game Config - At the Level Select screen Sound Test, play the following tunes in order: 00, 00, 00 to bring up the Game Config menu
- Debug Mode- At the Level Select screen Sound Test, play the following tunes in order: 01, 09, 09, 02, 01, 01, 02 and 04 to unlock Debug Mode. In order to open and close object placement mode, you must tap the HUD at the top-left of the screen. To exit to Level Select, you must tap the life count.
- Proto Palace Zone- At the Level Select screen Sound Test after enabling Debug Mode, play the following tunes in order: 03, 03, 03, 0B, 10, 10, 10, 04 and select Hidden Palace Zone.
There are a total of 12 Xbox Achievements/PlayStation Network trophies in Sonic the Hedgehog 2, totalling of 200G (Xbox 360 only).
Please note that Achievements are not transferable between Game Center on iOS and Google Play Games Services on Android.
|Quick Run||Complete Emerald Hill Zone Act 1 in under 35 seconds.|
|100% Chemical Free||Complete Chemical Plant without going underwater.|
|Early Bird Special||Collect all the Chaos Emeralds before Chemical Plant.|
|Superstar||Complete any act as Super Sonic.|
|Hit it Big||Get a jackpot on the Casino Night slot Machines.|
|Bop Non-stop||Defeat any boss in 8 consecutive hits without touching the ground.|
|Perfectionist||Get a 'Perfect Bonus' by collecting every Ring in an Act.|
|A Secret Revealed||Find and complete Hidden Palace Zone.|
|Head 2 Head||Win a 2P Versus game against a friend.|
|Metropolis Master||Complete any Metropolis Zone Act without getting hurt.|
|Scrambled Egg||Defeat Dr. Eggman's Boss Attack mode in under 7 minutes.|
|Beat the Clock||Complete the Time Attack mode in less than 45 minutes.|
- The English manual, which was released shortly after the Japanese version, simplified the storyline. It implied that the game instead took place on the same island as the previous adventure, and also altered Tails' character so that he had looked up to Sonic ever since he was a cub, showing off imitations of his role model's famous moves in front of the forest animals. Beginning with Sonic Adventure, the original Japanese storyline was adopted worldwide, and the localized storyline was virtually discarded.
- This is the only 2D Sonic game where the player doesn't get a "Try Again" message after completing the game without collecting all Chaos Emeralds.
- In the second trailer for Sonic the Hedgehog 4: Episode I, during the Sonic 2 section, Sonic's running animation from the Nick Arcade and Simon Wai prototypes is seen instead of the final version.
- The Debug Mode and 14 continues codes correspond to the English release date of this game (01, 09 ,09 ,02 ,01 ,01 ,02, 04 which is 24 November 1992) although the latter doesn't need the year.
- On the cover for the game in versions outside Asia, Robotnik's usual blue glasses appears to be depicted as empty black eyes. This could be the reason why the older Sonic television shows and comics portrayed Robotnik with black and red eyes.
- This is the first Sonic game to feature 2 Player mode.
- This is the first Sonic game to use the Spin Dash.
- This was the first main series game to have all seven Chaos Emeralds.
- This game was the Genesis' best seller due to the success of its prequel and the fact that the game was packaged with the Sega Genesis.
- In this game, there is a Super Sonic code that allows the player to obtain all Chaos Emeralds when inserting the level select code. This lets the player turn into Super Sonic with at least 50 rings without completing any Special Stages.
- When playing as Tails, Sonic flies the Tornado instead of him.
- This game is represented in Sonic Generations. Chemical Plant reappears as the second level of the Classic Era in the home version, while Casino Night appears as the second stage in the portable version. A remix of the 2-player results music can be heard while purchasing Skills in the Skill Shop. One of Sonic's wait animations, in which he looks at his wrist and lays on the ground, also returns as one of Classic Sonic's wait animations. Finally, the Death Egg Robot appears as the Gate Boss of the Classic Era in the home version. During the boss fight, a remix of the Death Egg Robot's theme can be heard.
- The app icon for the initial iPhone version of Sonic the Hedgehog 2 uses recycled artwork from Sonic Advance 2.
- Players are awarded with a "Perfect Bonus" of 50,000 if they complete an act after collecting every ring in the act and losing none. This is extremely difficult from Chemical Plant Act 2 and onwards, as acts will have more paths, some of which become unreachable after a certain spot.
- The ending theme of Sonic the Hedgehog (2006), Sweet Dreams, sounds very similar to the ending theme of this game.
- On the back of the American Sonic the Hedgehog 2 box, the screenshot of Sonic and Tails in the Oil Ocean Zone is actually a pre-release version of this zone. A switch can be seen on the right side of the screenshot. When pressed, it would release a large ball from the floor and roll right into the ocean (as seen in the Simon Wai prototype). The switch and the ball did not appear in the final version of this zone but can still be accessed in the Debug Mode in the final version. The screenshot of Aquatic Ruin Zone is also from a prototype version.
- In the U.S. instruction manual of Sonic the Hedgehog 2, page 7 has a screenshot of the title screen from the Beta 4 prototype. On page 9, the screenshot of the Oil Ocean Zone is also in from a prototype. Its background is different from the final version (most notably, the silver silo in the background is on the right side in the screenshot, but it is located on the left side in the final version).
- Interestingly, the sprite of Super Sonic used for the Super and Extended Super achievements is in fact a fan-made Sonic Battle sprite from a sprite sheet made by JoeTE.
- Boss Attack Zone in the 2013 mobile re-release was originally conceived as a complete one-act level called Egg Gauntlet Zone, which would have used new assets (as well as those from Sonic Crackers) to form platforming sections between each boss. Sonic Team did not agree with changing the location, colours or graphic style of the bosses, so Christian Whitehead deleted the zone in favor of the more direct boss endurance mode.
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 Sonic Team (1992). Sonic the Hedgehog 2 Instruction Booklet. Sega.
- ↑ Virtual Console Mondays: June 11, 2007. http://www.nintendoworldreport.com. Retrieved on 2007-10-21.
- ↑ Sonic the Hedgehog 2 on Xbox LIVE Arcade. http://www.xbox.com. Retrieved on 2007-10-21.
- ↑ Sonic Team. http://uk.games.ign.com. Retrieved on 21 October 2007.
- ↑ GameSpy: Sega's Yuji Naka Talks!. Gamespy. Retrieved on 27 February 2007.
- ↑ Kikizo Games: Features: Sonic Team Interview November 2005 (Page 2). Kikizo Ltd. Retrieved on 27 February 2007.
- ↑ 7.0 7.1 7.2 Thomas, Lucas M. (2007). IGN's Sonic the Hedgehog 2 Review. http://uk.wii.ign.com. Retrieved on 2007-10-21.
- ↑ 8.0 8.1 8.2 8.3 Provo, Frank (2007). Gamespot's Sonic the Hedgehog 2 Review. http://uk.gamespot.com. Retrieved on 2007-10-21.
- ↑ Daniel Boutros (2006-08-04). Sonic the Hedgehog 2. A Detailed Cross-Examination of Yesterday and Today's Best-Selling Platform Games 5. Gamasutra. Retrieved on 2006-12-08.
- ↑ 10.0 10.1 Game Zero Staff (1993). Game Zero's Sonic the Hedgehog 2 Review. http://www.gamezero.com/team-0/final_word/genesis/sonic_hedgehog_2.html.
- ↑ http://www.xbox.com/en-US/games/s/sonicxboxlivearcade/default.htm
- ↑ Sonic Retro Thread Page in which Christian Whitehead explains Egg Gauntlet Zone.