Hydrocity Zone (Sonic Mania)

From Sonic Retro

Sonic Retro emblem.svg Sonic Mania
Hydrocity Zone
  • Act 1
  • Act 2
Hydrocity Zone
Seventh Zone, Sonic Mania
Number of Acts: 2
Location: Angel Island
Level themes: underwater, underground/cave
Sub-boss: Dive Eggman
Boss: Laundro Mobile
Underwater areas: Yes
Non-English names:
  • JP: ハイドロシティ Haidoroshiti
Stardust Speedway Zone | Mirage Saloon Zone

Hydrocity Zone is the seventh Zone of Sonic Mania, which is based on Hydrocity Zone from Sonic the Hedgehog 3. The player is sent here from Stardust Speedway Zone by Phantom Ruby's power at Eggman's hands after the battle against Metal Sonic.


Unlike most other returning Zones in Sonic Mania, Hydrocity is designed in that all the new level designs and ideas are presented in Act 1, with the main gimmick being the water level being controlled by the player by pulling down certain hooks hanging from the ceiling. By adjusting the water level, the player is able to use other features such as boats to cross the water. In underwater areas, there are buttons that will release giant air bubbles that the player can ride in, much like in Game Gear titles like Sonic Triple Trouble. When riding the bubbles, the player can press Left or Right to move, Up to rise faster, Down to slow down, and any of the jump buttons to get out. Fans can push the bubble around, which is necessary for getting through certain spots.

Due to the new ideas being employed in Act 1, Act 2 is more straightforward in design, being based on the original Act 2 while having some level design from the original Act 1. All the features the player would come to expect from Act 2 return with the exception of the moving wall, and the addition of underwater currents that pull the player downward in a spiral.

Curiously, the backgrounds are swapped between both Acts, with Act 2's background now used in Act 1 and vice versa. In Act 2's new background, some of the walls have crumbled, revealing large cathedral windows.

Encore Mode

In Encore Mode, Hydrocity Zone's palettes have been changed that give the Zone more of a feel akin to Labyrinth Zone. The foreground walls have been given a more goldish hue, and the background colours have been changed the look more yellowish in Act 1, and reddish in Act 2. The water has also become more turquoise in colour.


Pointdexter — A spiked pufferfish. From the original Hydrocity Zone.
Jawz — A blue, flying shark robot. From the original Hydrocity Zone.
Mega Chopper — Red piranha that bites the player. From the original Hydrocity Zone.
Blastoid — Your standard cannon...Sonic style. From the original Hydrocity Zone.
Turbo Spiker — A red-wheeled vehicle with a spike rocket attached to it. From the original Hydrocity Zone.
Buggernaut — A blue mosquito that usually comes at the player in groups of three. From the original Hydrocity Zone.
Jellygnite — A jellyfish Badnik which floats in the water and tries to grab the player much like a Grabber. From Sonic the Hedgehog 2 (2013)'s Hidden Palace Zone.

References and Easter eggs

Reference Appears in Source Game Source Level
Pop in/pop out spears. Act 1, Act 2 Sonic the Hedgehog (16-bit) Labyrinth Zone
Jellygnite's appearance. Act 1, Act 2 Sonic the Hedgehog 2 (2013) Hidden Palace Zone
Levers opening new areas. Act 1 Sonic the Hedgehog 2 (16-bit) Mystic Cave Zone
Water tubes with strong currents. Act 1 Sonic the Hedgehog CD Tidal Tempest
Rideable giant bubbles operated by buttons. Act 1 Sonic the Hedgehog 2 (8-bit)/Sonic Triple Trouble Aqua Lake Zone/Tidal Plant Zone
The rising ground segment before the mini-boss fight. Act 1 Sonic 3 & Knuckles Marble Garden Zone/Flying Battery Zone
The reverse mini-boss fight to the original Hydrocity Zone's boss fight featuring attacking Dr. Eggman with his own vehicle. Act 1 Sonic the Hedgehog 3 Hydrocity Zone
Laundro Mobile's design based on the original Hydrocity Zone's Big Shaker along with the identical boss fight's second phase. Act 2 Sonic the Hedgehog 3 Hydrocity Zone
Dunkey's Secret Sound Effect. (removed in PC, Xbox One, and PS4 as of version RC 1.03.0919) Act 1, Act 2 videogamedunkey Dunkey's Best of 2016
Code to access the Dunkey secret sound effect is the same code used to access the level select in Sonic 3 & Knuckles. (removed as of version RC 1.03.0919) Act 1 Sonic the Hedgehog 3 & Knuckles/Sonic & Knuckles Angel Island Zone/Mushroom Hill Zone



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