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Sonic The Hedgehog Sprite Sheets - Sega Genesis - Sonic Galaxy.net

The Spriters Resource - Full Sheet View - Sonic the Hedgehog Genesis - Green Hill Zone

ArtStation - Sonic the Hedgehog Diorama Series: Green Hill Zone

Green Hill Zone, Map of the Sonic the Hedgehog video game universe Wiki

Custom / Edited - Sonic the Hedgehog Customs - Green Hill Zone - The Spriters Resource

Green Hill Zone Tileset by supersonic1009 on DeviantArt

Pixel Joint Forum: Sonic 1 Title separate BG sprites?

Neo Green Hill In Sonic Mania [Sonic Mania] [Works In Progress]

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

Sonic The Hedgeblog — Past Green Hill 'Tails & The Music Maker' SEGA