ArtStation - Mecha Sonic (Sonic 3 and Knuckles)

ArtStation - Sonic & CO

ArtStation - robotnic mech

[Speed Edit] Metal Sonic - Sonic the Movie

ArtStation - Mecha Sonic Model (Rendered in Substance Painter and Unity. Also including Wireframe in 3DS Max)

Speed Edit] Metal Sonic - Sonic the Movie

ArtStation - robotnic mech

Knuckles V.S. Mecha Sonic by MechaSonicSuperFan on DeviantArt

KREA - sonic the hegdehog fighting with ryu, highly detailed, 3 d render, artstation, artgerm, shinkiro toshiaki mori

ArtStation - Sonic The Hedgehog Aniversary 2015