Bing found the following results
Sonic the Hedgehog Cheats, Codes, and Secrets for Genesis
Sonic the Hedgehog – Game Genie Codes - Ethereal Games
Sonic the Hedgehog 1991 Cheats - Genesis Cheats Guide - IGN
GameGenie.com: Sega Genesis (Game Genie) Codes - Sonic the Hedgehog
Sonic the Hedgehog - Action Replay Codes [US] - Ethereal Games
Sonic the Hedgehog (Genesis) Cheats – RetroMaggedon Gaming
GameGenie.com: Sega Genesis Cheats - Sonic The Hedgehog
Sonic The Hedgehog GENESIS Cheats - Neoseeker
Sonic the Hedgehog Cheats For Genesis - GameSpot
Sonic The Hedgehog (Sonic 1) ALL CHEAT CODES - YouTube
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