Sonic the Hedgehog 2 (2013)

Sonic the Hedgehog 2
Developers: Christian Whitehead, Headcannon Publisher: Sega Platforms: iOS, Android, tvOS Released internationally: December 12, 2013 (iOS/Android), March 24, 2016 (Apple TV) This game has unused areas. This game has unused enemies. This game has unused objects. This game has unused graphics. This game has debugging material. This game has a hidden sound test. This game has a hidden level select. This game has revisional differences. This game has a bugs page

The 2013 version of Sonic the Hedgehog 2 is the third game in the Taxman/Stealth collection of remastered Sonic games. Like the 2013 Sonic 1 before it, the Sonic 2 remake replaces the rudimentary emulated version originally on the App Store and adds Knuckles, auto-match multiplayer, and wide-screen support and running on the fan-made Retro Engine.

The remake is most notable for including a completed version of the famed Hidden Palace Zone, accessible in normal gameplay... although it uses the 2-player Mystic Cave tune (like the Simon Wai prototype of the Genesis original) rather than the otherwise-unused Song #10 that plays upon loading the Zone in the final because they felt it was a better fit.

Besides the iOS and Android remakes of Sonic 1, Sonic CD, and a new version of Sonic 3 & Knuckles, this game is available in the Sonic Origins compilation.

Sub-Page

Bugs

Changes from the Genesis Version The image being fat now is just the tip of the IceCap.

Level Select/Debug Mode

The level select can be accessed the same way as in the 2013 Sonic 1 - start a "No Save" game and choose a character. On the SEGA logo screen, tap the letters S-E-G-A in that order once the entire word appears. If done correctly, you will hear a ring chime. Then hold two fingers on the bottom of the screen and wait. After the title screen appears, you'll be taken to the level select. Oddly, Hidden Palace is accessible, but only after beating it in a save game or exiting Proto Palace Zone (see below). Otherwise, trying to select it just makes a buzzing noise. Debug Mode does not change anything either, unlike a similar issue in Sonic & Knuckles.

If using a controller, press Up, Up, Up, Down, Down, Down, Left, Right, Left, Right at the title screen while in No Save mode.

Additionally, Tails' name can be changed to Miles by tapping the letters A-G-E-S on the SEGA logo screen. Or if using a controller, by pressing Up, Down, Down, Down, Down, Up on the title screen.

Game Config Menu

Play sound 00 three times in the Sound Test to bring up a "Game Config" menu. It replaces the more rudimentary menu from the 2013 Sonic 1.

• Player - Similar to the player select in the Genesis game's options menu, this allows you to play with Knuckles with Tails following, à la the default Sonic and Tails option.
• Items - Lets you choose between Sonic 2 items, hidden Sonic 2 items (all monitors display a "?" graphic), Sonic 3 items, and hidden Sonic 3 items.
• Flight - Toggles Tails' signature ability.
• Air Cap - Toggles the air speed cap.

Eighth Special Stage

Similarly to how the 2013 remake of Sonic 1 added a hidden seventh Special Stage, the Sonic 2 remake adds a hidden eighth special stage. By selecting sounds 00 through 07 in the Sound Test, you can change which Special Stage you go to. Playing sound 00 and selecting Special Stage takes you to Special Stage #1, 01 takes you to #2, and so on, with 07 taking you to #8.

The eighth Special Stage is purple, a color previously used exclusively in multiplayer Special Stages, and features corkscrew loops, possibly a reference to the Saturn Sonic 3D Blast's Special Stages.

Debug Mode

Play sounds 01, 09, 09, 02, 01, 01, 02, 04 (the US/European release date of the original Genesis game) in the Sound Test. During gameplay, tap the upper-left corner of the screen to access the debug mode. To change the item you are placing, press the + or - on the top of the screen.

You can return to the level select screen by tapping the lives counter in Debug Mode.

Selecting 2P VS after playing a No Save game with Debug Mode will allow you to enter a two-player game without connecting with another player online. While on the Stage Select screen, press Y on a physical controller, or L or 3 on a keyboard and a random character will join the game. The second player will always hang out at the starting point of a level, though, and will never move.

Developer Menu

Hidden inside the game is a normally unused Developer Menu. It allows you to choose any stage from the game, including the hidden Egg Gauntlet Zone. A similar menu exists in the Retro Engine remakes of Sonic CD and Sonic 1, as well as in Sonic Mania and Sonic Origins. It is accessed by going into the settings file and changing the devMenu variable from n/0 to y/1.

Unused Levels

Proto Palace Zone

After entering the debug mode cheat (see above), play sounds 03, 03, 03, 0B, 10, 10, 10, 04 and choose Hidden Palace on the level select.

This stage, added in Version 3.0.9, is the version of Hidden Palace from the Genesis original's Nick Arcade, Simon Wai, and August 21st prototypes. The level uses the otherwise-unused Track #10, as it does in the original game.

As with the stage's original incarnation, it's incomplete and stops at a certain point, although the water slide is now fully functional, among other minor changes. Rather than the "Master Emerald" acting as a breakable object, it instead warps the player back to the level select.

Dying in Proto Palace Zone will result in the game loading the used Hidden Palace Zone. Completing the stage by placing a signpost or capsule will send the player to Oil Ocean Zone, as was the case with the garbled version of Hidden Palace in the original game.

While a ring chime still plays upon entering the aforementioned code in the Sonic Origins port, Proto Palace Zone itself is inaccessible. This code and debug mode are now needed to access Hidden Palace Zone through the level select, which wasn't the case in the original mobile version.

Egg Gauntlet Zone

A scrapped boss attack level featuring some original artwork such as mechanical palm trees, as well as graphics from (of all places) Sonic Crackers. Sega did not approve of the level, as they did not wish for the bosses and enemies to be seen outside of their usual environments, and the level was scrapped.

The Zone was left fully playable, albeit inaccessible by normal means. It features all bosses in the game except for Brass Eggman and has no checkpoints (although there are rings between bosses). Unlike Boss Attack Zone, Egg Gauntlet features short platforming segments taken from the main Zones, as opposed to ones in Boss Attack that bear little to no resemblance to the Zones they are based on.

From v3.0.9, the stage itself and its bytecode (object code) were removed, effectively making the level unplayable. It was re-added since the Sega Forever re-release of the game, which can be selected under the "Bonus" section of the level select in the dev menu (along with Boss Attack Zone and Proto Palace Zone). "Egg Gauntlet Zone" is still referenced in StringList.txt. However, file names and some leftover code suggest that this level had an entirely different name in development: all the sprite files have the abbreviation "MBZ", and unused functions in the "MBZSetup" script reference the files "MarathonBase.ogg" and "MarathonBase_F.ogg". These .ogg files don't exist in the RSDK. Interestingly, the 2013 Sonic 1 also has code that references an unused Zone called "MBZ". The exact development timeline between these two games is unknown.

SwapMusicTrack("MarathonBase.ogg",0,635970,12650)

SwapMusicTrack("MarathonBase_F.ogg",0,5022294,7920)

Christian Whitehead explained why the level was cut from the game.

Regarding Egg Gauntlet:

Basically during development, we tried something different for the Boss Attack mode. Instead of the original bosses back to back, they were all in the one zone with connecting platforming sections - the idea being that it was a testing facility, with mechanical palm trees, flashing lights, etc. It was fairly close to completion (it just needed a few graphical effects, replacing placeholder graphics, and general polish), however, Sonic Team didn't agree with changing the location, colours, or graphic style for the Bosses.

So in the end we respected the wishes of the team and put together the Boss Attack you see today.

— Christian Whitehead

(Source: Sonic Retro)

Animations

Sonic's animation files list "Super Peel Out" as an animation, though it is unlikely that this move was planned since it is just random parts. What is interesting about these parts, however, is that they match up exactly with the Super Peel Out frame locations on the Sonic CD (2011) sprite sheet, suggesting that it was used as a base. Tails' Super Peel Out animation is his top speed animation, and Knuckles' animation has no frames.

Unused Sprites

Most of these are, unsurprisingly, leftovers from the original Genesis game.

Monitors

Artwork	Name	Description
	"S" Monitor	Makes the player Super and gives 50 rings when broken. Breaking this monitor is the only way for Tails to become Super Tails in this game. Unlike Sonic 3 & Knuckles, Super Tails don't have Super Flickies.
	Three Shields Monitor	Toggles the Items option when broken. Changes to the monitors will take effect when you restart the Act or advance to the next Act.
	Emerald Monitor	Breaking it will give you all the Chaos Emeralds, allowing you to turn Super with at least 50 rings. Breaking it again will take away the Chaos Emeralds.
	Spring Monitor	The only monitor that isn't used in Debug Mode. This monitor also exists in the Nick Arcade and Simon Wai prototypes.

Zone-Specific

Artwork	Zone	Description
	Emerald Hill Zone	The snail Badnik from the Nick Arcade and later prototypes of the original game can be placed with Debug Mode. It retains its behavior.
	Emerald Hill Zone	A prototype version of the Buzzer, now found in Debug Mode. This Buzzer behaves as originally planned in concept art, where its shots can burn bridges. The burning bridges are harmful unless the player has a Fire Shield.
	Chemical Plant Zone	This three-eyed fish Badnik is now fully functional and can be placed with Debug Mode. It flies around very slowly but will speed up if it sees the player, dropping Bubblers as it flies.
	Chemical Plant Zone	These are dropped by the Mother Bubbler Badnik, and will quickly explode after touching the ground. You can also place them individually with Debug Mode.
	Chemical Plant Zone	Can be placed with Debug Mode. These are merely decorations and do nothing.
	Chemical Plant Zone	Can be placed with Debug Mode. The fireball remains stationary but is harmful unless the player has a Fire Shield.
	Chemical Plant Zone	Can be placed with Debug Mode. The ball floats in the air and will chase the player if approached. When it's above the player's head, it'll explode and drop chemicals on the player that will hurt unless the player has a Bubble Shield.
	Chemical Plant Zone	This animation is still in the CPZ object sprite sheet but remains unused.
	Aquatic Ruin Zone	An unused door that can be placed with Debug Mode, which closes as soon as the player enters it.
	Aquatic Ruin Zone	A green Grounder that you can place with Debug Mode. This is most likely an homage to the version of Grounder seen in Adventures of Sonic the Hedgehog, a syndicated cartoon that debuted in 1993.
	Aquatic Ruin Zone	A strange pillar that doesn't appear anywhere else. Found in ARZ's sprite sheets.
	Mystic Cave Zone	An odd platform made of rings, which can be placed with Debug Mode. It can be stood on and moves in a similar motion to the spiked balls in the level.
	Oil Ocean Zone	The checkered ball can be placed with Debug Mode. However, it behaves like the rolling boulder from Green Hill Zone in the Sonic 1 remake rather than it did in the Sonic 2 prototypes and original game.
	Sky Chase Zone	The Balkiry's unused standing frame can, again, be seen through Debug Mode.
	Sky Chase Zone	Like before, the turtle's walking animation cannot be seen without the use of Debug Mode. This can be seen if you are in Egg Gauntlet Zone.
	Wing Fortress Zone	Can be placed with Debug Mode. It behaves like a Badnik, as it did in the original game.
	Wing Fortress Zone	A platform that shoots a laser when it spins. Can be placed with Debug Mode like in the original game.

Special Stages

Artwork	Name	Description
	"HYPER"	The Hyper form from Sonic 3 & Knuckles might have been planned to return, but was eventually cut. A similar graphic can be found in Sonic Mania.
	"GO TO HIDDEN PALACE"	It was probably required to collect all seven Chaos Emeralds to enter Hidden Palace (which was originally planned in the Genesis version) at one point in development, but in the end it was changed so you had to fall into the infamously inescapable pit in Mystic Cave Act 2.

Miscellaneous

Artwork	Description
	In the 16-bit version, Sonic had a transition frame when changing between the facing away balancing animation and the panicked one. This is barely noticeable because it’s only visible for one frame, and as such, it was forgotten about while developing in the remake. While the sprite itself is present in the files, it's never used in any animation.
	Sprites of Tails flying which bear resemblance to his "Fly Lift Up" animation, but with his head being lower, matching the position of his regular flying sprites. These are not used in any of his animations.
	Leftover continue screen animation for Tails from the 2013 Sonic 1 port. Tails use a different animation for the continue screen in this game.
	Leftover Tails life icons from the 2011 version of Sonic CD, present among Tails' sprites.
	Leftover timer marks, present among the HUD sprites. Another leftover from the 2011 version of Sonic CD.
	The default icon for sprites in Retro Engine's Scene Editor, is usually used for objects that aren't seen/spawned.

SEGA Forever re-release

On November 21, 2017, SEGA Forever, a service from SEGA, re-releases the game on Android and iOS in honor of its 25th anniversary. This version is also known as Sonic 2 Runner, because of the Package Name for the Android version game named com.sega.sonic2.runner. The last mobile version (3.1.5) was used as the basis for the re-release but with some differences.

General Differences

• The SEGA logo screen has been changed. Instead of a static background with the SEGA logo sound and design, now used is a video clip showing the SEGA Forever version of the logo.

Before SEGA Forever	SEGA Forever

• The game now asks for the age of the player when loading it up for the first time. This change remains exclusive to this version of the game.
• The game is now "free-to-play", but ad-supported. If the player does not buy the ad-free option, they will start the game with one life instead of three, and also will see ads between levels and after dying.
  • Getting a Game Over will also give you an ad pop-up.
    • If the player does not watch the ad, they will get a Game Over.

(Source: I-like-Sonic-91, Original TCRF Research)

• The game now supports UltraWide-screen formats and works on modern devices. If the player wants to play the old version on modern mobile devices, the game will not run in full-screen mode, instead either cropping or stretching the image. However, in the Sega Forever version, the screen area will be enlarged. This unfortunately creates some problems not seen in earlier versions.
  • Because of the enlarged screen, the player can see elements normally hidden from the player, because the game was originally created for smaller screens.

Player can see that Sonic did not leave until the end of the screen, which was not the case before.

• This version now supports new controllers. The old Android version of the game only supported MOGA Game Controller and MOGA Game PRO Controller for Android 2.3+.
• Now the Android version of the game uses Google Play Games service instead of Google+, as it was in older versions of the game.
  • Also, the button for connecting to SEGA servers is now missing.

Before SEGA Forever	SEGA Forever

• The Save Slot screen has become larger than it was in the old versions, but despite this, the screen has not been redesigned properly.
• The "Magazine" tab has been added to the menu.
• The About tab has been updated.

Before SEGA Forever	SEGA Forever

• The Settings tab has been updated.

Before SEGA Forever	SEGA Forever

Bugs

• The main menu now displays an incomplete version of the background, and that's because the background itself is made in 1024 by 512 pixels, but this bug does not work on all devices.
• Now, when the player activates Debug Mode at a level, a pause will be triggered, which was not the case in older versions of the game.