infinite return to be the penultimate villain of the series creating conflicts with his phantom ruby perfectly utilized aka reality warping shenanigans. he will be the constant force causing trouble in the world, binding his time until he get enough power to start his war which leads to several treasure hunting arcs for the powerful artifacts of sonic's world.

https://sonic.fandom.com/wiki/Phantom_Ruby#Powers_and_abilities

>sonic and crew are randomly teleported to the null zone
>they see infinite in the open emitting sounds/music from the games , his helmet vibrates like wearing headphones with mangeta light.
>starts look at sonic and crew start monologuing the following....
>SO LOOK AROUND AND TELL ME WHAT YOU REALLY SEE!
>BEHOLD PHANTOM CONTROL!
>MAGENTA LIGHT EVERYWHERE, FADE INTO DARKNESS
>reality warping nonsense follows