Knuckles is the guardian of the Master Emerald. Knuckles takes his residence on the floating Angel Island. He is known as a treasure hunter, but is a skilled martial artist as well. Knuckles is kind of a loner, who has had a rough past with Sonic. His cool attitude and echidna instincts leads him on his quest for jewels. He can be a true friend at times, but his strong personality and ego can conflict with that of Sonic's.
My take: Knuckles is one cool dude, who can sometimes play it cool. He can be a good friend, and is very loyal to protecting the Master Emerald. But, he has a short temper, and can sometimes be a bit brash on his decisions.
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