Casting rumors about the third season of "
Game of Thrones" have been swirling for weeks, and HBO finally put fans out of their speculation misery at Comic-Con by confirming the identities of more than a dozen actors who'll be joining the series in Season 3.Diana Rigg of the classic British series "
The Avengers" joins "
Game Of Thrones" as Lady Olenna Tyrell, "The Queen of Thorns." She is the grandmother of
the aristocrats Loras and ...