Genesis / 32X / SCD - Sonic the Hedgehog - The Sounds Resource

ArtStation - Sprite accurate Sonic The Hedgehog (16 bits).

Sonic the Hedgehog Game Genie Codes/Cheats, Video Game Hacking#

Custom / Edited - Sonic the Hedgehog Customs - Sonic (Sonic 1 Beta-Style) - The Spriters Resource

Steam Workshop::Sonic 3's Sonic Sprites in Sonic 1

Xeric on X: My Sonic 1 style set so far~ #sprites #pixelart

Sprites and Hoaxes – Shauniversal Studios

The Complete Sonic 1 Sprite Sheet (V1.0) by 123455675 on DeviantArt

FIND ME ON COHOST AND TUMBLR on X: i used existing sprites, both used and unused, from sonic 1, 2, and cd as pose references for all of these! the hurt-from-above sprite

Pixilart - sonic 1 ms sprites but i took them on as well by Tuxedoedabyss03

Adventures of Sonic 1, Sonic the Hedgehog Hacks Wiki