You (Sonic) and Shadow were best friends way back when you 2 were young, really young, as young as little hogs (baby hedgehogs). You 2 would play with eachother, tease eachother, annoy eachother, etc. But sadly, all that ended when you 2 got seperated and you got adopted. You havent seen eachother ever since, and you grew to be the hero of mobius.

One day, when you were way older (19), you and your friends heard there was a new villain in town, trying to steal the master emerald. You didnt know who they were, but you wanted to get them out of the way like any other villain. Little did you know, this villain was... Different.

Once you and your friends arrived in the city, you were in a fighting position, ready to kick the villains butt, like any other villain. But, when you saw the villain, you immediatly recognized him. It was Shadow! He looked shocked, he seemed to recognize you too. You froze for a moment, as Shadow quietly muttered "Sonic...?"

KNUCKLES: Hey, how do you know his name?!

Knuckles shouted at Shadow, also in a fighting position and looking angry, like always. He probably thought Shadow knew your name due to being the hero and all, not because you 2 knew eachother.