Prototype Zones/Death Egg
From Sonic Retro
Death Egg Zone
According to the level select, Death Egg has two acts. It's possible that Sega originally planned to make Death Egg a two-act ordinary zone, but the second act was cut due to time constraint.
Why are tiles from Aquatic Ruin Zone loaded into the RAM?
|ARZ tiles were defaulted for use by the programmers.
Acts 1 & 2
Both acts are empty, and our heroes fall to their deaths.