SPOILERS for ALL published books in the A Song of Ice and Fire series, and for Season 5 of Game of Thrones.
1. While enslaved, Tyrion becomes part of a private menagerie owned by a Yunkish millionaire.
2. Arianne Martell, daughter of Prince Doran of Dorne, conspires to crown Princess Myrcella as Queen of the Seven Kingdoms based on a loophole in Westerosi law.
3. It's not explicitly stated in the show, but true men of the North cannot become knights.
4. Brienne travels Westeros in search of a Stark, any Stark really, and ends up fighting a psychotic clown, meeting Gendry, and having half her face bitten off and eaten by a dude.
5. Sam conspires to make the men of the Knight's Watch vote for Jon Snow as Lord Commander.
6. Bronn gets married and names his wife's firstborn son after Tyrion.
7. One of Daenery's bodyguards literally takes a shit outside the walls of Meereen to warn the masters inside that this Kahleesi doesn't give a fuck.
8. Sansa helps Petyr Baelish keep his power in the Vale and becomes the acting Lady of the Eyrie.
9. Xaro Xoan Daxos comes to visit Daenerys in Meereen, and tries to give her enough ships to conquer Westeros on the condition that she leave Slaver's Bay alone.
10. Catelyn Stark's body is thrown in a river after the Red Wedding, but Arya Stark's direwolf Nymeria discovers her and brings her to dry land. Beric Dondarrion, the "immortal" knight who fought The Hound, finds her and brings her back to life.
11. Davos Seaworth travels to White Harbor, a Northern town, and is captured by House Manderly. They help him fake his death to appease Queen Cersei/The Boltons and come out as Stark loyalists.
12. Wyman Manderly also very likely kills three Frey men and bakes them into giant meat pies, which he then feeds to the Freys and Boltons at Ramsey Bolton's wedding.
Arienne Martell, Princess of Dorne and daughter of Doran Martell, plotted to crown Princess Myrcella as queen of the Seven Kingdoms. A previous version of this post stated that it was the Sand Snakes, illegitimate daughters of Oberyn Martell, who hatched this scheme. The author is sentenced to three months in the gaol tower at Sunspear.