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Sonic's adventure begins with him roaming the city at night after returning home from a long journey. He notices several police cars speeding to northeast section of the city. He decides to follow them. A monster has been discovered, and police are attempting to have it surrender. Their guns do not work on it, and they fall back. Sonic decides to take care of this problem himself.

[edit] Chaos 0

You will need to attack Choas 0 three times in order to defeat it. You may use the Spin Attack, the Homing Attack, or the Spin Dash to weaken it. There are 10 rings scattered across this little battle space and are found in groups of two.

At first, Choas 0 will attack by extending its arms towards you. Simply dodge these to avoid damage. After you have hit it two times, it will leap to surrounding poles and attack you from there. Eventually, it will come back down. Simply attack it from there to finish it off.

[edit] The god of Destruction

After Sonic defeats Choas, it will disappear into the sewer. Apparently, Dr. Ivo Robotnik (main villain of the Sonic the Hedgehog series, affectionatley nicknamed "Eggman" by Sonic & co.) has been watching the battle this whole time. He scoffs at Sonic, saying:

"You know nothing fool! It's Chaos, the god of Destruction!"