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Sonic the Hedgehog (Classic), Fictional Characters Wiki

Super transformation, Sonic Wiki Zone

GameCube - Wikipedia

Sky Sanctuary (Sonic Generations), Sonic Wiki Zone

Death Egg Robot (Sonic Generations), Sonic Wiki Zone

Sonic the Hedgehog, Sonic (universe) Wiki

Sonic Adventure 2 (Video Game) - TV Tropes

Sonic, Fiction Database Wiki

The Dark Side of the Moon - Wikipedia

Sonic the Hedgehog (film)/Transcript, Sonic Wiki Zone

Animal echolocation - Wikipedia

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