Chemical Plant Zone (Sonic Mania)

Chemical Plant Zone is the second Zone in Sonic Mania. This Zone is a re-imagination of Chemical Plant Zone from Sonic the Hedgehog 2 for the Sega Mega Drive.

Overview
Like the original Zone, this Zone is set in an industrialized area that contains pools of various synthetic chemicals, most prominently Mega Mack, as well as long tubes. Act 1 in particular bears a strong to the original Chemical Plant. Act 2 on the other hand goes deeper into the plant to an indoor section, with large beakers and jars present in the background. New additions to Act 2's setting also include gelatinous chemicals, sticky platforms and chemical bubbles.

Story
Having been teleported to the Chemical Plant Zone when Dr. Eggman got his hands on the Phantom Ruby, Sonic, Tails and Knuckles began their trek through the Zone to catch up to Eggman. At the end of the Zone, the trio overcame Eggman and his final challenge, although the doctor managed escape. In response, Sonic and co. pursued him out of the Zone through the pipes.

Gameplay
Like the original Zone, Chemical Plant Zone has blue chemical jets that shoot indestructible balls of blue Mega Mack from one tube to another, or in a parabolic path; these require very quick reflexes, as touching this Mega Mack will cause damage. There are also yellow-clad pipes filled with blue chemicals that spiral through almost the whole map. These pipes can have very steep drops and may climb after a drop. There are also collections of yellow/purple squares that move back and forth periodically. The player must use these blocks to scale vertical shafts, which requires a knowledge of the game physics and quick reflexes.

New to this Zone are pools with hot-boiling Mega Mack that damage the playable characters upon contact, and pools of gelatinous caustic chemicals called "jelly". Landing on the surface of jelly pools causes the player to bounce upward, similar to a Spring. The color of the jelly pools determines the height of the bounce; blue ones create small bounces and green ones crate large bounces. In some places, there are also large syringes with which the player can inject new chemicals in nearby pools by standing on their plunger. This will change the pools into jelly in different color.

There are also strange gelatinous purple pads set on the walls and ceilings around the Zone. Touching these pads makes the playable characters cling to them until they jump off. These pads may also slide along the surfaces they are placed on, allowing the player to ride them to different areas of the Zones. In addition, there are purple bubbles pushed upward by DNA strand-shaped Mega Mack springs that can carry the player up to higher areas.

The Zone has the original Zone's High-speed warp tubes, miscellaneous terrain features that suck the player in and deposit him/her at the other side of the tunnel, that wind across the Zone. In Sonic Mania, these tubes come in new shapes, and the player can choose which tube to follow at intersections.

Act 1
Act 1 remains true to the original Chemical Plant Zone. It incorporates the level layout from both Acts of the original, featuring winding passageways, pipes, harmful chemical balls, and slopes on which the playable characters can reach full speed. New additions include a new bottom route and Metallic Madness-style pipes where the player can choose their own path.

The pools of Mega Mack also return, including the infamous "rising pool" from the original stage where Sonic must escape from a vertical shaft with shifting block platforms that fills up with Mega Mack or risk drowning (and unlike the original version, the shaft fills up faster than Sonic can ascend so it is inevitable the player will be trapped under the liquid).

Act 2
Act 2 introduces many of the new stage gimmicks and also features a new background. The helix lifts, the sticky sliding platforms, and the bouncy jelly pools all appear in this Act. In addition, the intertwined tube chutes that originally appeared in Carnival Night Zone are present, although they are translucent instead of opaque.

Act 1
A machine similar to the Iceball miniboss from IceCap Zone will plunge into the blue chemicals underneath the floor the characters are standing on. It will sway back and forth, collecting a stock of chemicals, before rising up and bouncing on the floor. After this, it will hover in the air and spin the chemicals around itself like the Ice Ball miniboss before scattering them and restarting the process. The boss can be hit when the chemicals are spinning around it.

Act 2
The boss of Chemical Plant Zone Act 2 is a battle against Dr. Eggman in a game of Puyo Puyo/Dr. Robotnik's Mean Bean Machine.

The fight follows very much the rules of the original game: the player must connect at least four Beans together in order to make them disappear, causing a Refugee Bean to appear on Eggman's side. The goal is to overwhelm Eggman with Refugee Beans, causing his Bean stack to reach the top of the screen. The player will win when the third Bean stack from the left has completely filled up where Eggman can no longer place Beans, causing his side to break away, leading Eggman to fall down a bottomless pit.

Because of the random nature, the time limit is frozen for the duration of the battle.

Trivia

 * The Chemical Plant Zone features several references to past Sonic media:
 * The animation of Sonic shaking off the dampness caused by the falling drop of Mega Mack at the beginning of Chemical Plant Zone Act 1 is similar to the animation used for Sonic at the beginning of Toxic Caves in Sonic the Hedgehog Spinball.
 * The high-speed warp tubes in Chemical Plant Zone Act 1 and 2 (which let the player choose their path) are similar to those seen in Metallic Madness from Sonic the Hedgehog CD.
 * Chemical Plant Zone's Amoeba Droid bears a strong resemblance to the Iceball (the sub-boss of IceCap Zone in Sonic the Hedgehog 3), except it rotates and levitates chemicals instead of ice.
 * Catakiller, Jr., an enemy that appears in Chemical Plant Zone Act 2, was originally an enemy in Angel Island Zone from Sonic the Hedgehog 3.
 * The jelly pools that bounce Sonic up make the same sound effects as the electrified floor in Wacky Workbench Zone from Sonic the Hedgehog CD, and work in a similar way.
 * The coiled and translucent tubes in Chemical Plant Zone Act 2 are similar to those seen in Quartz Quadrant from Sonic the Hedgehog CD and Carnival Night Zone from Sonic the Hedgehog 3.
 * The groups of blocks in Chemical Plant Zone Act 2 that lower themselves when hit from underneath appear to be based on those that appear in Star Light Zone from the original Sonic the Hedgehog.
 * The music for Chemical Plant Zone Act 2 has samples of Metallic Madness' music from Sonic the Hedgehog CD (JP version) in it.
 * The Act 2 boss of Chemical Plant Zone utilizes the signature gameplay style from the Puyo Puyo series and the spin-off Sonic title, Dr. Robotnik's Mean Bean Machine. It also features a remixed version of the track "Final of Puyo Puyo"/"2 Player vs.".
 * On Sonic Channel, this boss battle was hinted as a "surprise ending" to Act 2.
 * UnusedTailsChemicalPlantcutscene.gif Both Sonic and Knuckles have special intros when entering this zone, where a drop of purple water falls on their heads and they react to it. However, in Tails's case, he does not react to it when it falls on him despite having an animation for this event in the game files where he blows off the Mega Mack with his twin-tails.

Videos
Act 1 (E3 Demo) = Act 1 & Act 2 = Act 2 (E3 Demo) = Act 2 =