This article is too damned short, Marine! You will help Gruntipedia by so it will fit the screen, fool!
A Katana is a unique and retarded Armor Permutation that is unlocked by wasting your life playing Halo 3 until you get over 9000 gamerscore. It is probably magnetized to a Spartan's armor or maybe it is placed in a socket like a some toy. Even though it looks like awesome weapon to slice Noobs, it cannot really be used because some people don't want to add all the cool stuff in one game so they can get money in the next game. They also make you want to yell banzai.
For some reason, the Katana sometimes randomly locks and unlocks. So, if you had a Katana and were showing it off to your friends yesterday, it might be
stolen locked by the Bungie Ninjas. A easy way to unlock the Katana and the Security Shoulders without gaming a lot is to help Bungie and quickly buy the Mythic Map Pack early. Though, some say this is what Bungie says to gullible people.
Bungie had the idea to do this because they played Ninja Gaiden for two days and 31 minutes. After Team Ninja knew about the idea stealing they started to say "NI!" in order to force the Bungie Ninjas to steal peoples katanas. However, they always try to return them, explaining the locking/unlocking.
Rumour has it that Chuck Norris killed the Prophet of Nerds with a katana just because he said that Star wars was better than Halo. Chuck Norris chopped the Prophet into small bloody chunks with the katana, threw him into the explosion of Alpha hula hoop and went to go do his weekly errand, your mother.