Sonic the Hedgehog is a remastered version of the original Sonic the Hedgehog for the Sega Mega Drive/Genesis on the iOS and Android mobile platforms. The game was first announced by Sega on 26 March 2013. It was released on 15 May 2013 for iOS and on 16 May 2013 for Android. The iOS version is also a free update to those who purchased the earlier iOS port of the game. It was developed by Christian Whitehead and Headcannon using the Retro Engine, the same game engine used for the 2011 remastered version of Sonic the Hedgehog CD.
The gameplay remains generally faithful to the original Sonic the Hedgehog but it runs at a stable 60 FPS, has widescreen support and a remastered soundtrack. In addition, the game has received new features and gameplay changes.
- The Spin Dash is now included as an optional move.
- Despite not being officially introduced yet in the series, Miles "Tails" Prower and Knuckles the Echidna are unlockable characters, with mild tweaks to the level design to accommodate their gameplay. They both retain the same movesets they had in Sonic the Hedgehog 3 & Knuckles. Tails can also accompany Sonic like he did in Sonic the Hedgehog 2 and Sonic the Hedgehog 3 & Knuckles.
- Tails is unlocked by completing the game once while Knuckles is unlocked by completing the game with all six Chaos Emeralds.
- While playing as Sonic (or Knuckles) and Tails, the player is able to control Tails' flight by pressing jump while holding up. Sonic can then jump onto Tails' arms and control Tails to fly around until he tires or lands on solid ground.
- A hidden seventh Chaos Emerald and Special Stage was included via Level Select.
- Another "custom" Special Stage is accessible via Level Select where it can be designed and edited by the player using Debug Mode. Once saved, it will then become the current seventh Special Stage that will override the default seventh Special Stage.
- A Time Attack mode is included.
- The hidden Level Select and Debug Mode options are greatly expanded, taking elements from the sequels as well as incorporating recreations of unused content.
- The life count is now displayed at the top-right corner of the screen as opposed to being located at the bottom-left corner of the screen.
- The title screen now changes based on the player's characters. As such, it can alternatively display Miles "Tails" Prower in Sonic the Hedgehog (for Tails alone), Sonic the Hedgehog & Tails[note 1] (for Sonic and Tails) or Knuckles the Echidna in Sonic the Hedgehog (for Knuckles alone, originally created by Stealth in 2005).
- Spikes on the wall and Rings in the air that can only be reached by Tails or Knuckles have been added above the Lamppost between the two S-tunnels near the end of Green Hill Zone Act 1.
- The boss of Green Hill Zone has a wider arena and also, Dr. Robotnik can no longer be prematurely attacked until the wrecking ball has been fully deployed.
- At Marble Zone Act 1, climbing or flying to the top of the wall now reveals an Invincible Item Box. When climbing/flying to the top of the wall at Marble Zone Act 3, a new passage is implemented from there.
- At Special Stages, the stages now rotate smoothly.
Reception to this version of Sonic the Hedgehog has mainly being positive. David Oxford of Gamezebo, who gave a rating of 4.5/5, praised the game's new features, sound quality and the customisable d-pad but still felt that the virtual controls can be tricky. Also, the inclusion of Tails and Knuckles seem to "feel slightly out of place". In addition, he has also noted a few bugs and oddities. Chris Buffa of Modojo, who also gave a rating of 4.5/5, similarly agreed with the touch control issue.
- Level Select and Sound Test: Start a game in "NO SAVE MODE". At the opening Sega logo, touch the letters S, E, G, A in that order. If done correctly, a chime will sound. When the title screen appears, press the screen with two fingers at once or just hold them on the screen. You will be taken to a new level select screen, very similar to the one from Sonic the Hedgehog 2. One can change their playable character, Spin Dash options, speed cap options, and Spikes options (activating the old lack of invulnerability for spikes or not).
- An alternate method to unlocking Level Select is by using the gamepad: On the title screen, press Up, Down, Left, Right. If done correctly, a chime will sound.
- All Chaos Emeralds: Go to the Level Select Sound Test and play the following tunes in this order 04, 01, 02, and 06 from the Sound Test.
- Super Sonic: On the Level Select sound test, perform the All Chaos Emeralds code then change the Max Emeralds setting from 6 to 7. Sonic can transform to Super Sonic after collecting 50 Rings in any stage. You should replay the All Chaos Emeralds code first. This can be used for Super Tails and Super Knuckles.
- Play any Special Stage: At the Level Select Sound Test, play a tune between 00-07 inclusive. Then select Special Stage.
- Debug Mode: From the level select, play sounds 01, 09, 09, 01, 00, 06, 02, and 03 in that order from the Sound Test. After starting a level, tap the GUI in the top-left corner of the screen to activate/deactivate Debug Mode.
- Character Select: From the level select, change the player option from 00-03. 0 is Sonic and Tails, 1 is Sonic, 2 is Tails, and 3 is Knuckles.
- Change Tails' name to Miles - When the Sega logo appears, tap the letters A-G-E-S in that order. This can be done either in starting a new game normally or in No Save Mode. This applies to Tails' life count and the title screen will change to Sonic the Hedgehog & Miles.
- The music of Metallic Madness Past from Sonic the Hedgehog CD was used during the mobile remastered versions' trailer.
- At the Sega logo, if the player taps the letters A-G-E-S, then instead of the "SONIC TEAM PRESENTS" screen, the player is treated to a screen displaying hidden credits in Japanese as seen in the image to the right.
- The Debug Mode code (01, 09, 09, 01, 06, 02, 03) is a reference to the release date of the original release date of Sonic the Hedgehog (23 June 1991).
- This port marks the first game since Sonic Advance 3 that Knuckles can be accompanied with Tails.
- The secret level select used the style and background of the ones in Sonic the Hedgehog 2. The words in the background change from "Sonic" to "Miles" and back, despite the fact that Tails is only unlocked once the game is beaten.
- During gameplay, a notification pops up every now and then to say "Thank you Sonic! But the chaos emeralds are in another zone!". This is a callback to the original Super Mario Bros. where upon completing one of Bowser's castles, Toad says the infamous line of "Thank you Mario! But the Princess is in another castle!".
- Not to be confused with Sonic & Tails, the Japanese name of Sonic Chaos.
- Richard Mitchell (16 May 2013). Sonic the Hedgehog speeds to Android today. Retrieved on 2 April 2015.
- Andrea Gil (26 March 2013). Sonic the Hedgehog announced for iOS and Android. TSSZ. Retrieved on 2 April 2015.
- David Oxford (21 May 2013). Sonic the Hedgehog Review. Gamezebo. Retrieved on 2 April 2015.
- Chris Buffa (20 May 2013). Sonic the Hedgehog iPad Review. Modojo. Retrieved on 2 April 2015.
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