To make it even weirder, the going theory right now, is that Gerald Robotnik based shadows design off of a mural on angel island prophesying about supersonic. So Shadow might actually be based off of sonic before sonic even existed.
FACT: SONIC THINKS SHADOW CHEATS WITH HIS JET SHOES.
FACT: SONIC THINKS HE'S THE ORIGINAL FAST HEDGEHOG.
FACT: SHADOW IS TWICE SONIC'S AGE CHRONOLOGICALLY. FACT: WHEN SHADOW TAKES OFF THE INHIBITOR RINGS ON HIS CUFFS, THEN IT GIVES HIM GREAT POWER AND STRENGTH. POSSIBILITY: IF SHADOW TAKE THE INHIBITOR RINGS OFF HIS ANKLES, THEN HE MIGHT BE GRANTED SPEED REACHING SONIC'S. QUESTION: WHO'S THE ORIGINAL FAST HEDGEHOG? GO FIGURE.