The black Sonic represents Dillon, an anthropomorphic armadillo who appears as the Assist Trophy enemy.
The stage and music track represent the post-apocalyptic setting of Dillon's Dead-Heat Breakers, which features a Western setting.
Sonic's favored special moves references Dillon's ability to roll, which can be used to attack enemies similar to Sonic's special moves.
Other trivia:
This spirit's Attack type and Speed ↑ ability references how Dillon attacks by rolling into enemies, which allows him to gain speed.
