Pixilart - A detailed Sonic 1 sprite by Diam0nddude

Sonic the Hedgehog (8-bit video game) - Wikipedia

Sonic the Hedgehog (1991) - MobyGames

Tried to draw Sonic as accurately to the Sonic 1 sprite as

Sonic 1 & Knuckles - SEGA Online Emulator

Sonic 1 HD OST (Windows) (gamerip) (2013) MP3 - Download Sonic 1 HD OST (Windows) (gamerip) (2013) Soundtracks for FREE!

Release][N3DS] Sonic 1 & 2 (2013) Decompilation port

Sonic 1 Styled Knuckles [Sonic the Hedgehog Forever] [Mods]

Sonic 1 TTS 1990 Demo (Sprites Remake) by DevyOfficial on DeviantArt

Prerelease:Sonic the Hedgehog (Genesis)/1990 Tokyo Toy Show - The Cutting Room Floor

I'm learning to use the SGDK, I made these edits for Sonic 1 and 2 (I'm going to use the Sonic 1 palette). The Sonic 3D sprite I made just for practice!