The mishima family is cursed, so basically...in the first game, Kazuya is the good guy, but once the devil gene takes over, he is bad or morally grey all the time. Jin is then introduces as a new hero, but the same thing happens to him. None of them are really heroes beyond the game they are introduced. (tekken 1 and 3,respectively)
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I'm "kind of a big deal".
http://img.imgcake.com/cyclo/Cyclopngegpngre.png