Gaius was also able to make himself stronger with some sorta Magitek buff, causing his armor and weapon to glow a golden color. I don't remember if Regula did that but this now makes me wonder if we have even seen Zenos's final form!

Also something I just thought of that isn't part of the trailer, but with Red Mage's back jump attack is the first X-Cross attack we have gotten access to I think. One step closer to Garlean job!