Sonic The Hedgeblog — Back in 2015 the mobile game 'Angry Birds Epic

Back in 2015 the mobile game ‘Angry Birds Epic’ had a ‘Sonic Dash’ event where Sonic would join the battle. This even had some unique renders only made for the event.

Sonic the Hedgehog, Angry Birds Wiki

Sonic The Hedgeblog — Back in 2015 the mobile game 'Angry Birds Epic

Sonic The Hedgeblog

Angry Birds Epic RPG - Gameplay Walkthrough Part 9 - Halloween 1-10 (iOS, Android)

Sonic the Hedgehog, Angry Birds Wiki

Sonic The Hedgeblog

Angry Birds Epic: Sonic Dash Event #3 - The Giant Buzz Bomber

Angry Birds Meets Sonic The Hedgehog by CobyMaverick on DeviantArt

Angry Birds Epic RPG - Gameplay Walkthrough Part 15 - Northern Slingshot Woods (iOS, Android)

Angry Birds Epic “Sonic Dash” Special Event

Sonic the Hedgehog, Angry Birds Wiki

Angry Birds Epic RPG - Part 10 [Walkthrough] [HD] [Gameplay]

Sonic Dash - 4, Angry Birds Wiki

Sonic The Hedgeblog