Seeing how that scene with the dragons ended in the book, I was really worried for Tyrion for a moment…

"The End and the Beginning", I wonder if it's related to Ice Prince Finn's proclamation that he's "The End and the Beginning, I am the hand of madness"

It was rather predictable that Tim would turn out to be a hallucination, what was surprising is that unlike the previous "visions", Tim isn't just reflecting, he's making actual conversation, and he's saying everything will be all right. A message from whatever's sending these visions?