Game of Thrones has been groundbreaking TV for over seven years with unpredictability and the ´nobody is safe´ plotline doing away with multiple major characters along the way, most of which have been shocking and unexpected especially for those who haven´t read the books by GRR Martin. As expected, with any very popular thing that has unexpected twists and turns, gamblers will find a way to bet on things. Political elections, sporting events, groundhogs… if there is something where the outcome is at chance, people will gamble. The same has been true of Game of Thrones the last few years where Bovada and a few other online gambling sites have allowed betting on such topics as who will be the next major death, who will kill other major characters and of course, who will ultimately sit on the Iron Throne.
In the early days of Game of Thrones before some newcomers became aware, book readers would often set up sucker bets because they knew the outcome and would bet against people who were not aware the show was based on a book. But now that the TV show has outpaced the books, betting on deaths and murders is much more unpredictable, even moreso because even in places where the books are ahead of the TV show, the TV show has gone its´own path.
All of that ended near the end of July when HBO was hacked and the hackers were able to obtain both the scripts and the actual episodes allowing many viewers to see episodes days before they aired. Of course this complicates things if you are trying to create a fair gambling environment. So because of the leaks, all of the online casinos and websites that were offering gambling have no stopped accepting new bets, even for some events that will not be determined for another year or two. This risk of a leak that is not rapidly detected by the casinos could result in uncapped amounts of safe bets made by people who obtain the leaks.
For what it is worth, Jon Snow is favored to be the one sitting on the throne at the end of the last episode with Dany coming in a close second. Jaime leads the options as the one who kills Cersi, but only time will tell.