This is the first franchise in the game to have originated in the East, as most of the franchises in the game are Western properties.
The Sonic the Hedgehog franchise was leaked early by a well-known leaker.
Before this, Sonic the Hedgehog was leaked in a list of product codes from September 2015, labeled as S and due to the singular letter, most speculated that it would be more characters from The Simpsons, however, it actually referred to the character of Sonic himself.
The year that this franchise was announced and released for LEGO Dimensions was 2016, which happens to be its 25th anniversary.
This is the first franchise from Year 2 that connects to the story mode via a level pack or story pack.
This world has the most music tracks, with 19 total. With the exception of the drowning theme, music tracks for the areas from the Genesis titles have been replaced by sound-alike tracks, as the rights to the originals are held by their respective composers and have to be licensed separately for use in games, even by SEGA. SEGA owns the rights to all music created from Sonic Adventure onwards, however, allowing for LEGO Dimensions to use tracks from games such as the Adventure titles and Sonic the Hedgehog 4.