Despite never being referred to in the books as the Purple Wedding, the wedding of Joffrey Baratheon to Margaery Tyrell has become well known as this by the fans. Of course we had the Red Wedding during season three, and although the death toll in the Purple Wedding will be a little bit more precise than seen in the previous wedding, it does tend to suggest that Westeros weddings are quite, quite deadly. We'll see the Purple Wedding very early on, somewhere between the first and third episodes. We all get to watch Joffrey choke to death on a poisoned glass of wine, which sets into play a serious of actions in King's Landing that I've previously mentioned in this list. Tywin Lannister subsequently blames Tyrion for Joffrey's death. Tyrion had a successful trial by combat the last time he was accused of murder and decides that it'll be a good idea to do that again... This results in the fight between Oberyn Martell and Ser Gregor Clegane, with Martell representing Tyrion and Gregor fighting for Tyrion's execution. As I said before, the results of the fight has repercussions for everyone involved and the entire series. Because deaths resulting from that fight will result in the Martells seeking to bring Daenerys Targaryen to Westeros. The thing is, Tyrion had nothing to do with the death of Joffrey... The plot thickens. Bring on the new season!