Okay so crazy idea what if Vanitas is going to be one of the vessels for the thirteen hearts of darkness now here is why I say this in KH 2.8's trailer we see the Ventus/Vanitas go in to one of the seats plus every one has wondered why we saw Vanitas behind young Xehanort but he could already be a part of them and he was just in hinding reforming this could explain the lingering spirt of Vanitas and this is either a back up plan made by Xehanort or Vanitas now this is just a theory but I believe Vanitas will come back very soon so please support or critize to your hearts content