ok heres the deal:
asuka is jin's daughter with an unknown girlfriend. she has most of the same moves as jun her grandmother from tekken tag.
jin hates his kazuya and heihachi so he unlearned mishima style fighting and learned karate on tekken 4, although he does hav some similar moves to before eg. laser scraper, rising uppercut which is f, d, df square instead of triangle etc etc.
jinpachi is heihachi's father, he broke free of his chains when heihachi's place got blown up and supposedly heihachi died but he didnt.
deviljin is the same as devil mixed with jin from tekken tag. they mostly gave him jins moves but some for example the laser beam are devils.
i dont actually have the game so i dont know much about it but i do play at the arcade nearest my house and the rankings go down not up eg 9th, 8th, 7th etc etc.
might i also point out that asuka isnt that great, she just looks good. if you knew how to play as jun on tekken tag she was much much better.
my personal favourite is law he is very similaer to before with some new better juggles. although the character who in my opinion is potentially the best is hwoarang. i cant actually use him myself but i have play this guy who can who seems to use never ending juggles that are extremely powerful and its quite annoying lol. if you need any more information about the stories of tekken 5 just check out the official website:
http://www.tekken-official.jp/
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