Sorry if this was discussed somewhere else...
Young Shujinko is the guy you build up in Konquest mode. I'm guessing you can go through Konquest and choose 2 fighting styles and a weapon for your cahracter to have and gradually obtain specials (spear, ice, etc) as shown in the Boon video. This would make sense that by the time you age to old Shujinko, Konquest mode ends and you can now use him in other modes as Old Shujinko, using the styles and specials you've obtained.
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