Sonic goes to green hill zone for a vacation but when he get there he sees robotic things called badniks. Sonic soon finds they were made by a mad scientist called dr. Robotnik/eggman who attacks sonic but sonic beats him by jumping on platforms and hitting his machine.

So eggman escapes and sonic goes after him soon sonic reaches the final zone and fights eggman and wins. Eggman runs away and sonic goes back to green hill zone and is congratulated by the flickies.

Sonic decides to go on a vacation to emerald hill zone where he meets his soon to be sidekick miles tails prower or tails. Sonic and tails see robotnik and sonic decides to stop him before he unleashes his plan with the death egg. 

Sonic and tails reach the final zone but tails gets shot down luckily he's okay. Sonic ventures on and soon encounters a robot called meta sonic and destroys him then he goes after robotnik and beats his machine.

Sonic falls from the sky but is caught by tails and he does signature pose. With tails in the background.

Sonic and tails decide to go on a vacation to a floating island called Angel island zone but soon meet a new frienemy called knuckles a powerful guardian of the master and steals the chaos emeralds. 

They soon get to eggman and beat him.

Sonic and tails continue and soon fight knuckles who is soon after betrayed by doctor eggman who steals the master emerald and apologies for stealing the emeralds so he takes them to sky sanctuary and beat mecha sonic and eggman.

Sonic is bored and decides to go on a another vacation he calls tails but tails is busy so he goes solo but he soon finds out that eggman has stolen a planet called little planet and sonic decides to go in there where he meets his self proclaimed girlfriend amy rose who is kidnapped by metal sonic.

Sonic goes to speed highway zone and metal sonic is destroyed and sonic saves amy goes after eggman and defeats him and the little planet is safe.

Meanwhile knuckles meets a group of geeks called vector charmy ray mighty and espio who enlists them to help him and he makes them team chaotix and they defeat metal sonic and save the world.

Sonic soon meets mighty and Ray and they get captured and taken to a secret base where they have to escape and defeat doctor robotnik which they do.

Sonic then encounters eggman and has to go through a pinball kind of thing first in toxic caves. He soon encounters eggman again and defeats him.

During all these events tails is saving creatures in two of his games.

Sonic and co find out that eggman has moved to a city and go after him. They find out that a chaos emeralds protecty thing named perfect chaos has been taken and turned evil by eggman.

Tikal a good natured echidna soon meets them and tells them that a long time she met perfect chaos who was just a normal chao and they become friends but soon eggman kidnaps him and takes him away to his base and perfect chaos is turned from good to bad.

Now has to perfect from destroying the city while big looks for froggy and amy meets a badniks called gamma.

They defeat eggman and perfect chaos is sent to the temple to live in peace once again.

Sonic is soon arrested for some reason and escapes and he races through a city where he meets the ultimate life form shadow and he's soon put in prison again. 

Meanwhile knuckles meets a bat called rouge and breaks the master emerald into pieces and he and rouge go on a treasure hunt spree to see who can get the most pieces.

Sonic and shadow have a final battle and sonic wins he and soon form a truce and defeat eggman and shadow remembers what Maria actually said and falls to his doom. 

then There are games like sonic labyrinth sonic r and sonic drift.

Anyway so sonic and co go after eggman to defeat him and save the world their in. So the story is spilt into four stories:

Team sonic: sonic tails and knuckles from eggman and go and stop him. They eventually do and sonic is chased by Amy.

Team dark: rouge is looking for eggman's secret treasure and runs into shadow in a pod and both are attacked by a badnik named omega and soon form a team and rouge finds out shadow has lost his memory and he and co soon after with finds out shadow is not a robot.

Team chaotix:vector charmy and espio are relaxing when a unknown person tells them about a mission which is worth lots of money if they succeed so they go but find out the unknown caller is eggman and attack him.

Team rose:Amy big and cream are on the pier relaxing and soon go to find chocolachoa and froggy and they do.

The game then has a finale story with all four teams who find out metal sonic has planned to destroy them all but is defeated by the teams and every one is safe.

Soon sonic tails and knuckles run into a team called babylon rogues and they decide to race them