Sonic's Friendly Nemesis Knuckles #1

Mobius contains numerous wonders, including the mysterious Floating Island, containing the Chaos Emeralds. These Emeralds are protected by Knuckles the Echidna, who comes from a long line of Echidna guardians. The Echidna culture, once a technologically sophisticated society, has since disappeared, replaced by wilderness in the Floating Island, all that remains of their group. However, beneath the great Mount Fate lies clues to this past.