There's an extra special stage that can be accessed through the sound test menu by setting all the 3 selections to 07. According to a former Sega Europe QA Tester, an extra Time Stone was to be collectible here. When collected in addition to the previous Time Stones, "S" TV monitors would appear where the ring TVs were previously located. When broken, Sonic would morph into a lesser version of Super Sonic, which would simply grant invincibility and greater speed. Graphics would not change.