According to Kotaku, Darth Vader and Yoda have been confirmed to be playable characters in the next and final iteration of the Soul Calibur franchise.  No definitive word on whether there will be any more hidden Star Wars characters.  I would imagine Darth Maul would be an easy favorite.

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I expected as much of Dead or Alive, not a stranger to special guest stars of Spartic proportions.  Soul Calibur’s non-sensical "storyline" is even stranger than the gobbledegook in Dead or Alive.  Neither have any ties to reality I suppose but I always imagined Soul Calibur as the spiritual successor to Eternal Champions as far as storyline is concerned.  Some sort of an afterlife battle.

Tekken, surprisingly enough with its fighting (harassment) Panda’s, is now the most "realistic" fighting game.  A worldwide fighting tournament is a valid excuse for bringing all the world’s greatest fighter’s together.

Soul Calibur?  Fighter’s from a galaxy far, far away?  With force powers in a game that is known for its swordplay not fireballs?  No choke move fatalities, no lightning.  I think they should just redo Masters of the Teras Kasi using a successful fighting engine and a well known development studio.  Do the game justice.

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A Star Wars fighting game COULD be fun, if done right.