Second review. This game locked onto Sonic 3 makes this one of the best platformers ever!
The story of this game takes place after the events of Sonic 2, Sonic and Tails leave on their tornado, to investigate Angel Island. Along the way, they meet a troublemaker, Knuckles the Echidna. Knuckles is really just trying to protect his Island, because Robotnik tricked him into believing Sonic is the bad guy. Now, what's changed since Sonic 2? Well, you have a very helpful move called the insta-shield. You jump, then press the jump button again to use it. It's good for hitting bosses that are just barely out of your reach. You find other shield power ups, the fire shield, the thunder shield, and the water shield. The fire shield lets you do an air dash, to get some speed going, and protects you from fire based attacks. The water shield prevents you from drowning, and let's you do a bouncing ball attack, much like a power up in Sonic Adventure 2. The thunder shield protects you from rare thunder based attacks, sucks in nearby rings, and allows you to double jump, making it the most useful shield.
Chaos emeralds are back, but we are introduced to a new set of jewels, the Super emeralds. Chaos emeralds are the same as they were in Sonic 2, they let you turn into Super Sonic. But the Super Emeralds allow you to turn into a form that we will never see again, Hyper Sonic. Hyper Sonic has all the abilities of the shields. He can air dash, he can breath under water, and he can double jump. The final boss various depending on how you played the game. If you didn't get any set of emeralds, you get the bad ending, if you only got the chaos emeralds, you fight an extra boss, and get a good ending. If you got all 14 emeralds, you fight the extra boss and get the perfect ending.
If you're a Sonic fan, or just a fan of platformers in general, play this game as soon as you can. Download it on the Wii, play it on an emulator, do whatever you can to play it. No one should pass up the chance to play this gem.