no not for arcade mode
You can't unlock jinpachi in tekken 5. He's usable if you chance upon him picking random characters. He is unlockable in tekken 5 dark resurrection, though.
Scenario Campaign. As you go through, you will unlock characters. play as them in the arena mode
Beat the game with every character.
Beat the game with the original characters in order to unlock him.
Well, Tekken 5 DR is much cheaper than Tekken 6 at the moment. In Tekken 5 DR, you start with all of the characters so if you want all of them to start with go for Tekken 5 DR. If you already have Tekken 5 for PS2, then you should get Tekken 6.
you unlock jinpachi can in tekken 5 (dark resurrection) but in the normal tekken 5 you cannot unlock him.
No, you can play as every character in the Tekken series, you can even play as some brand new characters.
There is a patch called Street Fighter X Tekken 1.06 that one can download to unlock other characters. Run the setup program and install it and copy the file, const.lua under the StreetFighter boot game folder.
Kazuya Mishima is the main character of Tekken 1 & 4, Heihachi Mishima is the main character of Tekken 2 (Although the events in Tekken 2 revolve around Kazuya's actions), and Jin Kazama is the main character of Tekken 3, 5, & 6.
There are no characters in Tekken 6 that are cousins. There are only father-son and half brother relationships in Tekken 6. The new character, Lars Alexandersson is the half brother of Kazuya Mishima from Heihachi Mishima.
Devil/Angel. To do so, unlock all characters, then play through with kazuya
one way to do it is by beating devil within