Sonic The Hedgehog 3 & Knuckles (lost build of cancelled iOS port of Sega Genesis platformers; 2014)
Sonic The Hedgehog 3 is a Sega Genesis title released in 1994, that became a hit with fans and critics alike. Unfortunately, due to cartridge storage limitations and time constraints, almost half the content had to be cut from the final product. The removed content would later be re-purposed into Sonic & Knuckles, which could "lock on" and give extra content to the player when connected to Sonic 3. This created Sonic 3 & Knuckles, which is the complete and intended way to play through both of these games.
In 2011, Christian Whitehead (a prominent figure in the Sonic fan community, going by the name "The Taxman" online, who was best known prior for creating the fan game Retro Sonic) was hired by Sega to make an iOS port of Sonic CD using his handcrafted Retro Engine which recreated the physics of the original Genesis games. When it was released, it became a hit with fans and critics, later being ported to PlayStation 3, Xbox 360 and Steam.
Two years later in 2013, Christian was hired once again by Sega to port both Sonic 1 & 2 to iOS, this time joined by Simon Thomley (another well-respected member of the Sonic fan community, going by the name "Stealth" online, best known prior for the fangames Sonic Megamix, Sonic the Hedgehog GBA and Knuckles the Echidna in Sonic the Hedgehog). Both the Sonic 1 and Sonic 2 ports did really well, helped by all of the new content added to the game by Christian and Simon.
Sega, hoping to follow up on this trail of success, commissioned them to port Sonic 3 & Knuckles to iOS. However, when the port's development began, legal issues arose with one of the composers, Brad Buxer, who did not want his work to be used. This hindered the project from continuing.
As of now, neither files from the game have or the IPA file itself have resurfaced or leaked. Neither Christian Whitehead nor Sega has given any word on the port's potential cancellation.
The only known footage from the iOS port comes from a 2:44 video from Christian and Simon released in October 2014 on YouTube, showing the proof of concept in action. This video showcases the game running on an iPhone, featuring Sonic and Knuckles running through a remade version of the game's first level, Angel Island Zone Act 1. Various versions of the Blue Spheres special stage also appear, along with the Slot Machine, Gumball Machine and Glowing Spheres bonus stages. The video is set to a remix of the Angel Island Zone Act 1 music by composer Tee Lopes, who would later collaborate with The Taxman and Stealth on 2017's Sonic Mania, composing the score for the game.
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