This simple patch replaces the final character sprites with the ones seen in early prototypes of the game, with all extra frames of animation fully ported over.
Database match: Sonic The Hedgehog 2 (World) (Rev A)
Database: No-Intro: Genesis (v. 20180824-045026)
File/ROM SHA-1: 8BCA5DCEF1AF3E00098666FD892DC1C2A76333F9
File/ROM CRC32: 7B905383