Comment faire pour débloquer les personnages se...

En les battants en mode tournoi.
Apres la final on peut les affronter mais ils sont ultra fort !

Il faut réussir le tournoi sans que l'ordi ne gagne de point. D ou moins bien == King, C ou mieux == Duke.

Source si tu sais lire l'anglais :

Duke and King

To unlock Duke and King enter Tournament mode and choose singles matches. Beat the tournament without the computer winning a game. ( not point ) Depending on your Ranking you will be challenged by either Duke or King. Total of D or worse gets you King, total of C or better gets your Duke. Beat the challenger to unlock that player. For an easier time change settings to "very easy" and 1 game sets. Duke and King are hard so get good with cross court and slam shots.