PAX Prime was this weekend, and with it came an absolute flurry of Magic and Tarkir-related activity, including, of course, a ton of card spoilers, all of the clan-specific keyword mechanics revealed, some crazy revelations about the story, and much more. I'll be covering that in more detail soon, but as a good rumormonger I'm as forward-thinking as I possibly can be, which is why I'm so excited about the next set after Khans of Tarkir, now known to be called Fate Reforged.
The sets in this block are known not to be taking place in strict chronological order, and the promotional artwork shows Sarkhan in full Mardu battlegarb, with fiery, draconic energy flowing through him - perhaps indicating that this is the moment of his ascendancy as planeswalker. If that's the case, Fate Reforged takes place in Tarkir's near past, possibly with a storyline involving Sarkhan avoiding the clutches of Bolas and saving the life of the late ancient planeswalker and recently voice in Sarkhan's head, Ugin.
Other hints indicate that perhaps, since Fate Reforged isn't a wedge-themed set, the story could be about a world where the clans never formed. In any case, if the final set is called Dragons of Tarkir, we're all definitely in for a wild time.