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Sonic Mania/Unused Graphics - The Cutting Room Floor

Sprites and Hoaxes – Shauniversal Studios

Steam Workshop::Sonic 1 - Green Hill Zone

Green Hill Zone Sprites Mania by Alex13Art on DeviantArt

Sega Genesis / 32X - Sonic the Hedgehog - Green Hill Zone Objects - The Spriters Resource

Green Hill Zone Tileset by supersonic1009 on DeviantArt

Green Hill Zone Expanded by UltraEpicLeader100 on DeviantArt

Mania Madness Ep. 1 Preview Green Hill Zone W.I.P. (Sprite Animation)

Knuckles' Chaotix, knuckles Chaotix, Green Hill Zone, tilebased Video Game, Sonic Mania, Sonic the Hedgehog 2, cyan, Sprites, Tails, sprite

The VG Resource - Dolphman's sprite library of customs & edits