Blame George R.R. Martin. It's his fault for embellishing his world with the kind of rich detail that makes you think everything is a hint or a knowing wink. Since people can adopt puppies and watch them die of old age between the release of each book, voracious fans have had no recourse but to fill those years by digging through existing material and continuing to fill out the world with their own ideas. Game of Thrones fan theories has now usurped pornography as the thing that takes up most of the internet. It's to the point where a lot of these theories are stale, or just accepted as fact. It's no longer controversial to say Ned Stark isn't Jon Snow's father, Tyrion is a Targaryen or Stannis Baratheon is secretly a praying mantis.
So instead of going over the more popular suppositions, we decided to dig up some of the more obscure fan theories that still have a hint of credibility. If you haven't read all of the books, this is spoiler country.
There's a big moment in the fourth book, a Feast for Crows, that explains a ton about Cerse Lannister's motivations. It comes when Cersei remembers a day from her childhood, the day she employed the services of a not-at-all sketchy fortune teller called Maggy the Frog. When Cersei asked if she would one day be a queen, Maggy warbled through the phlegm in her throat: "Queen you shall be... until there comes another, younger and more beautiful..." *hocks loogie* "...to cast you down and take all that you hold dear." Since one of Maggy's other, very specific predictions came true, Cersei has been paranoid about this beautiful usurper for years. That's why she's been such a dick to Sansa Stark and Margery Tyrell.
But Maggy's most stirring wart-fueled prediction describes Cersei's death: "And when your tears have drowned you, the valonqar shall wrap his hands about your pale white throat and choke the life from you." So she's got that goin' for her.
Most of the Maggy-related discussions center on just who the murderous "valonqar" will be. Cersei hates Tyrion's Emmy Award-winning guts, so she assumes that he's the one that plans to strangle her. She does have a good reason, beyond all the unfounded venom -- the word "valonqar" translates from Valyrian-Klingon to "little brother", which applies to Tyrion in more than one way. But it can't be that obvious, so the next in line is Jaime Lannister -- he's Cersei's twin, but technically born after her, hence "little brother." Jaime becoming the valonqar and killing Cersei would be a fitting end to a tumultuous relationship.
But wait, Maggy said that Cersei would be killed by "the valonqar," not "your valonqar." Which leaves the door wide open for...
Yep, cute little Tommen. Adorable and innocent as he is, it's possible that the mounting pressure of the throne could drive him to inbred madness, causing him to snap and strangle his own mother. Then again, Maggy the Frog did reference Cersei's future children "Gold shall be their crowns and gold their shrouds," indicating that she'll see her children die. And maybe she will. But by then it will be winter. It's very possible that her son's corpse will rise again as a white walker and put her in a permanent sleeper hold.