Gigalopolis Zone, shortened to Gigapolis Zone in the international Sega Game Gear version, is the second Zone of Sonic Chaos for the Sega Game Gear / Sega Master System, coming after Turquoise Hill Zone and preceding Sleeping Egg Zone. In keeping with the other stages of this game, Gigalopolis consists of two standard Acts followed by a shorter, third Act which contains the Zone's boss. Geographically, this Zone is located on South Island (as is the rest of Sonic Chaos).
This level sees Sonic and Tails run through an urban environment at night, under the stars. Some of the level resembles a construction site, with orange, metal frameworks and seemingly incomplete block walls. The background displays various high-rise buildings and oftentimes the sea as well. This Zone also introduces the 3/4 loops in the Game Gear series, which were first shown in Sonic the Hedgehog's Star Light Zone.
A major gimmick introduced in this Zone are diagonally-inclined bridges. In order to cross these bridges, the player must be running at high speed, otherwise they will slip off and fall.
Gigalopolis is one of the only zones in Sonic Chaos to have two different music tracks for the Game Gear and Master System versions respectively.
|Smash through walls with the Super Spin Dash. Watch where you jump, or Dr. Robotnik's traps will make you a chump! Metal-o-Turtles and bugs are out to get you. Fight the Bead Worm Boss to clear the zone.
— US Game Gear version manual
|Lights glitter on the night skyline as you spring from level to level. Race through corridors, then jump on top and grab those Rings!
— EU Master System version manual
|A futuristic city with ultra-modern buildings “Gigalopolis” …With the beautiful star-filled sky in the back, Sonic & Tails go on a big rampage! Dash across the diagonally-inclined bridges to cross them.
— JP Game Gear version manual (translation by greenyvertekins)