Sonic 3 & Knuckles Part 1: Angel Island Zone (Sonic & Tails)
Whether it's Sonic 3, or Sonic 3 & Knuckles, this game takes place after Sonic the Hedgehog 2.
Previously in Sonic the Hedgehog 2, Sonic, with the help of the 7 Chaos Emeralds, has defeated Dr. Ivo "Eggman" Robotnik in his Death Egg, causing it to collapse. Sonic then becomes Super Sonic and escapes the exploding Death Egg.
The Death Egg didn't explode, however. It was just badly damaged, and landed on a massive floating island known as Angel Island. The obscene weight of the Death Egg causes Angel Island to fall right out of the sky and sink very slowly into the ocean.
That's where this game's new character, Knuckles the Echidna, comes in. He is the last member of his own near-extinct tribe, and serves as the guardian of Angel Island and its source of power: The Master Emerald. When the Death Egg causes the island to sink, he heads out to investigate.
On the other side of things, Sonic, and his fox buddy, Tails, caught wind of Eggman's new activity on Angel Island, so they fly to that island to see what he's up to now.
Unfortunately, Knuckles got to Eggman, first, and Eggman tricked him into thinking that he's the good guy, and that Sonic & Tails were the villains. Knuckles then teams up with the Doctor, and his first act of service towards him is to use his amazing strength to knock an eager Super Sonic back to his normal state. He then takes the Chaos Emeralds from him and hides them in mysterious dimensions known as Special Stages.
Now, Sonic the Hedgehog and Miles "Tails" Prower must travel through the different regions of Angel Island, take back the emeralds, defeat Robotnik once again, and make Knuckles realize that he's playing for the wrong team.
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This first video will focus on getting the first four Chaos Emeralds alongside getting through Angel Island. There should be a total of 4 Special Stage rings in the entire zone, 2 in each Act.
Follow how I got Perfects on the first four Special Stages as I go through them if you don't know how to accomplish that on your own.
Chaos Emeralds & Their Special Stage Field Patterns:
Green - Brown & Orange
Orange - Dark Green & Mint
Pink/Purple - Vanilla & Orange
Blue - Red & White
Try remember each Special Stages' two colors and the Emerald each of them contain to help you out with the different layouts you'll have to go through.
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After Knuckles steals the Chaos Emeralds, Act 1 of Angel Island Zone has Sonic & Tails traveling through a lush jungle, with rhino and monkey Badniks ready to take them down.
Halfway through the act, they run around the inside of a giant hollow log, where they get greeted by Eggman's latest flame-throwing creation. It bombs the entire jungle and sets it ablaze! Who could've ever seen this coming? This will last for the rest of Angel Island Zone.
Starting with Sonic 3 (& Knuckles), almost every zone's Act 1 will have its own boss alongside Act 2. Act 1's boss is a big machine Eggman made, and Act 2's boss is a fight with the Doctor himself, sometimes riding in a more powerful version of his Act 1 machine.
Also, after you beat an Act 1 boss, you start Act 2 right where you claimed your victory, and now Act 2 is introduced with a remix of the Zone's Act 1 theme!
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Not too many people know this, but at the very end of Act 2, you can move again as soon as Knuckles presses the bridge-destroying button. You can even backtrack to the ground you were just on, but, even with Tails, you won't be able to reach Knuckles. Some kind of invisible wall is right in front him.
Just fall down the waterfall like the game had it scripted as and move on to Hydrocity.