Sonic Chaos/Hidden content
From Sonic Retro
Extra Tiles in Opening Cutscene
In the opening cutscene, a sprite of Tails running can be found in the VRAM. However, when Tails is eventually revealed, he's walking, not running. Could it be possible that he was meant to run along with Sonic rather than walk after him when he goes off-screen?
Unused Music
When accessing the Sound Test feature in the game, the song titled "BGM#09BH" can be heard, but was not used in the game. The track was later used in Sonic Triple Trouble as the Sunset Park Act 3 song.
Fireball
In the Sound Test screen, Sonic can shoot a fireball by pressing , then or .
Game Gear version
Master System version