I bet it was Varys.

So, uh, trailer spoilers? As you can tell from the shoddy picture quality and slightly angled shot of the screen, this is a recording of an as-yet-unreleased HBO trailer for Game of Thrones Season 5. The next season might not revisit all the characters (there are two books—no spoilers—that happen at the same time but follow two separate sets of characters), but the ones who are in this trailer, particularly Daenerys, Varys, Tyrion, Cersei, Arya and Jon, look like they're in for dangerously exciting levels of plot.