Scrambled Egg Zone

Scrambled Egg Zone is the sixth (and potentially final, if you haven't been collecting the Chaos Emeralds) zone of the Game Gear/Master System Sonic 2. As with all other stages in this game, Scrambled Egg Zone consists of two standard Acts followed by a shorter, third Act which contains the Zone's boss.

As with its predecessor, Gimmick Mountain Zone, Scrambled Egg appears to be part of a hollowed-out mountain which Eggman has sculpted for his own nefarious purposes. Blue rocks and dark, yawning caverns abound, illuminated by the pitiless blinking of Robotnik's linear light arrangements. The zone is riddled with winding transport tubes, many of which dump Sonic unceremoniously into spike pits unless you have your wits about you.

Unlike all the preceding zones in Sonic the Hedgehog 2 (8-bit), Scrambled Egg does not have a Chaos Emerald hidden away in some secret location. To obtain the 6th and final gem, you must defeat the boss.

Boss
After a lengthy upwards journey by tube and spring in Act 3, Sonic fights one of his first battles against his erstwhile robotic doppelganger. Silver Sonic flies around the arena with rocket shoes and (non-damaging) spin attacks.

If you've collected the 5 Chaos Emeralds from previous Zones, Silver Sonic explodes on the final hit, dropping the yellow emerald (which Silver was presumably using as a power source). This enables Sonic to proceed into the final zone, Crystal Egg Zone. However, if you did not collect the Chaos Emeralds, you do not go to Crystal Egg Zone.