Namco Bandai Games Europe has posted a FAQ on their website officially confirmed the Edo Kage, Kinkaku, Ginkaku, and the six missing Ninja Swordsmen of the Mist will not be playable in the game. They’ve stated it isn’t possible to include them through downloadable content (DLC)
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Some third rate characters that had barely any meaning to the story in the first place are not going to be added in as playable. Still a great game even with a couple of the characters not being playable.
lol j/k lol. it's cause namco gave false hope thats why we everybody is angry. if they said something before and not released fake-me-out scans all would have been better. but they showed scans and videos activating like they were in it and not saying anything until a week AFTER the game was released.