User blog comment:LuxrayBlast/Shadow and Team Chaotix for 5mash/@comment-32618542-20180323224044/@comment-32618542-20180325165745

If Sonic is playable again, then Shadow would still be an assist trophy. As for Knuckles, the protagonist of Knuckles’ Chaotix? He’s still a no-go. According to Sakurai, only one third-party character from a third-party series can be playable, and that’s Sonic from the Sonic series.