Tails flies Sonic to visit Angel Island. When they arrive at the island, Knuckels, the guardian of the island attacks Sonic and steals the Chaos Emeralds. As it turns out, Dr. Robotnik crash landed on the island after his Death Egg was destroyed. He has convinced Knuckels that Sonic is the bad guy and must be stopped. As Sonic and Tails fight to stop Robotnik latest evil plans, they must get past Knuckels as well. Written by
Did You Know?
was invited to return to compose for the game as he did for the first two Sonic the Hedgehog games, but when Nakamura asked for a higher salary as well as compensation fees for any music reused in future titles, Sega decided to turn to other composers instead. See more
When the countdown begins to notify the player that Sonic is running out of air in Hydrocity Zone when fighting the mini-boss, if Sonic replenishes his air, the music will switch to the mini-boss music from "Sonic & Knuckles". This also happens during the fight with Robotnik in the same Zone. See more
If the game is finished with all the Chaos Emeralds, dolphins can be seen following the plane in which Sonic and Tails are riding. Complete the game without all the Chaos Emeralds, and there are just birds following the plane. See more
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