Check out the Final trailer for Duodecim

In the trailer, some of Yuna's moves are revealed. The original grid map from the first game makes an appearance. What appears to be Cid from XIII (but I'm actually not entirely sure) makes a quick appearance in the trailer. A mysterious villain from FFIV also makes a quick appearance but only through voice and a darkening cloud in the sky. Aeris is also a support character now.

This video is in the japanese square-enix website, so you'll have to enter the compendium and then click on video.