Hydrocity Zone (Sonic Mania)

Hydrocity Zone is the seventh zone in Sonic Mania. This Zone is a re-imagination of Hydrocity Zone from Sonic the Hedgehog 3 for the Sega Mega Drive.

Overview
Like the original, this Zone is a water-filled underground system with fans and blocks.

Story
After escaping Little Planet, Sonic, Tails and Knuckles have arrived in the Hydrocity Zone during their mission to get the Phantom Ruby away from Dr. Eggman. Midway through the Zone, the team got back at Eggman with his own Egg Mobile when he tries to escape them. Sonic and co. also manage to escape Eggman's final trap at the end of the Zone, although the egg-shaped scientist again eludes capture.

Gameplay
Most of the sections in Hydrocity Zone are underwater, so this requires the player to go slow and steady.

Act 1
Act 1 is an obvious recreation of Act 1 of the original, but harder. There are gimmicks from other zones too (etc, Labyrinth Zone) and canoes that is accessible for areas above water. Eventually, the player will get to a part where they can see Dr. Robotnik swimming, where they will fight the boss.

Act 1
The boss battle "begins" with a short cutscene of Doctor Eggman wearing a scuba outfit deploying bombs that cause the water level to rise, initiating a short segment where the player must avoid being crushed inbetween the rising ground and the ceiling. After the segment, the player jumps into an Egg Mobile with the Waterspout and Depth Charge attachment. The player must use the Egg Mobile to suck up Eggman and damage him with the machine's blades while avoiding sucking up the bombs he deploys. After four hits, Eggman's scuba suit explodes and he falls off the screen in defeat.

Act 2
Act 2's boss battle begins with Eggman using a propeller to blow the player rightwards underwater. During this phase of the battle, the player must avoid spikes coming from the right side of the screen and activate bombs coming from the same direction. Hitting Eggman with the bombs damages him and produces an air bubble for the player character to catch their breath and is the only way of staving off drowning during this phase of the battle. After six bomb hits, Eggman's propeller breaks and the battle changes to a regular platforming battle that mimics the Whirlpool Machine from the original Hydrocity. After eight hits, the battle is over.

Trivia

 * The prediction of Hydrocity Zone being in Sonic Mania started from a tweet from Lucas Carvalho on Twitter. He made a picture of Knuckles running through Hydrocity, but it was later deleted and changed to Flying Battery Zone.
 * This Zone is harder than the original, only because it is played through later in the game.
 * A secret feature can be unlocked in Hydrocity Zone by performing a specific set of actions. While hanging from a hook, input the following command: left, left, left, right, right, right, up, up, up (the Sonic the Hedgehog 3 & Knuckles level select code). The sound effect of a Ring will play upon successful entry. This code changes the sound effects produced by the speed boosting machines.