Sonic The Hedgehog 3 & Knuckles (cancelled iOS port of Genesis platformer; 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, some 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.
In 2011, Christian Whitehead (a prominent figure in the Sonic fan community) was hired by Sega to make an iOS port of Sonic CD using his handcrafted Retro Engine. When it was released, it became a hit with fans and critics. Two years later in 2013, Christian was hired once again by Sega to port both Sonic 1 & 2 to iOS, which both became successes. Sega, hoping to follow up on this trail of success, commissioned him 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's from continuing.
As of now, neither files from the game have or the IPA file itself has resurfaced. Neither Christian Whitehead nor Sega has given any word on the port's potential cancellation.