To all those saying that Tommen in the season 6 promo looks puffy faced and thus likely being poisoned:
No, the actor simply has puffy cheeks that are over-pronounced when he wears a turtleneck. The kid should avoid high colors whenever possible as he otherwise looks like a chipmunk.
Lol. I think you're right. It is the collar.
"I can see it. You have more of the north in you than your brothers."