What is the Ruby Theory for Game of Thrones?

It has something to do with each Ruby, all seven, representing the descendants of Aerys II in Westeros. To keep things short: Rhaegar wore an armor with rubies that made up his House Sigil. In the Battle of the Trident, Rhaegar got smashed in the chest by Robert's warhammer. read more

As I remember the theory is that there are multiple ruby pendants in play and there has been a bit of face swapping. Tormund is pretending to be Mance, Mance is pretending to be John, and John is the pimp. read more

The most crackpot theory I've seen about it is that she will use the ruby to make Jon Snow look like Rhaegar Targaryen and claim the Iron Throne. That's basically insane since he probably has a good claim without the looks, but with the looks people wouldn't know who this new guy is. read more