As is traditional at PAX Prime, the fall large set trailer - Khans of Tarkir, of course, this year - premiered over the weekend, and now is available on YouTube. Here's what we've learned from it:
Sarkhan has returned home with some cryptic things to say as an introduction: "Some were born to fight. Some were born to rule. I was never born at all." What this exactly means is still up for debate, but maybe we're looking at some kind of "grandfather paradox" situation (kill your ancestors and you prevent yourself from being born, and also hence from killing yourself and preventing... you get the idea) since this is a time travel story.
He basically avoids two important subjects entirely: Why he's back on Tarkir, and the titular Khans of Tarkir themselves, except as the very last word he says. He pays lip service to the idea that both Bolas and Ugin have guided him.
Since this is an intro to a new world, the script has to have him describe the most important feature - the five wedge-color clans. He calls the Mardu fierce horsemen, who travel quickly and have quicker tempers. The Jeskai he says are disciplined, intelligent, and enlightened. The Sultai are decadent and subtle overlords who line their palaces with stolen treasure. The Temur are ferocious foes who are close to nature, and the Abzan are the ultimate survivors - "surprisingly hard to kill." All of this was already known, but interestingly he has nothing worse than grudging praise to say about any of the clans.
All in all, this is the best looking trailer yet, since there now appears to be a budget for full animation, instead of merely the "motion comic" style of past trailers.