Sonic Colors Ultimate Brings in Metal Sonic for Rival Rush - Siliconera

Sega detailed Sonic Colors Ultimate improvements and additions in a new trailer, and Metal Sonic will appear for a Rival Rush mode.

Sonic Colours Ultimate - Metal Sonic Rival Rush

Doctor Eggman Sonic News Network+BreezeWiki

Sonic The Hedgehog - A Little Ball of Energy in an Extremely Handsome Package

Sonic Colors Ultimate: How to Unlock Rival Rush

Sonic Mania: Most Up-to-Date Encyclopedia, News & Reviews

News - July, 2012

Rival Rush with Metal Sonic, customizations highlighted in new Sonic Colours Ultimate update - Tails' Channel

Rival Rush with Metal Sonic, customizations highlighted in new Sonic Colours Ultimate update - Tails' Channel

Review: Sonic Colors Ultimate is yet a Pretty big Sonic Game - Game News 24

Review: Sonic Colors Ultimate is yet a Pretty big Sonic Game - Game News 24

Trest ― Perchance Generator

Sonic Colors: Ultimate review -- Reaching for the stars