Fan Casting Post Credit Scene in The Great War: A Dawn of Sonic story

This takes place after Robopocalypse. In fact, at the very volcano where Eggman perished, there is a USB drive on a rock ledge near it, it must have been launched out of there before Metal Robotnik melted. Then a mysterious figure with a weird gem on his hand grabs it. Cut to later and the figure plugs in the drive into a computer. The figure comes into the light once the monitor flashes on and all you hear is static. We see a platypus with a weird hairdo grin at the screen, saying “Why, hello. My name , . . is Dr. Starline.”