Sonic Chaos

Sonic Chaos (known as Sonic & Tails in Japan and Sonic the Hedgehog Chaos in Europe) is a video game for the Sega Game Gear and Sega Master System, developed by Aspect and published by Sega in 1993.

It was re-released in 2004 as an included game in Sonic Mega Collection Plus on the PlayStation 2, Xbox and Windows, and is also included as an easter egg on Sonic Adventure DX: Director's Cut for the Nintendo GameCube and PC. To unlock the game, the player has to collect 60 emblems as all of the playable characters.

Sonic Chaos is notable for the fact that it is the first 8-bit Sonic title to feature Tails as a playable character, and also the first in the series to allow the player to manually control his flight.