In a “leaked clip” revealed by the folks at Conan, George RR Martin let slip several surprising “spoilers” while recording episode commentary for Game of Thrones.

George RR Martin appeared on Conan earlier this week, and now the show has revealed a “mysteriously leaked DVD commentary for Season 4 of Game Of Thrones.” The video clip contains some wild information, so viewers of the show (and readers of A Song of Ice and Fire) may want to proceed with tongue-in-cheek caution!

Among the shocking spoilers revealed by Martin in the clip were a surprising future for Joffery (the psychotic teenaged king “adopts an adorable lion cub and learns the true meaning of Christmas”) and an unexpected cameo from “long-lost cousin” of Winterfell and creator of the Iron Throne, Tony Stark. Meanwhile, Jaime Lannister will form “Kingslayer,” the first heavy-metal band in Westeros.

Martin also shared plans for the future of Game of Thrones, including talking dragons and a complete reboot of the show which will recast Daenarys Targaryen with Zachary Quinto. And even the weather will herald surprises for fans. “Winter comes,” Martin announced. “It’s not so bad. Cozy!”

“Hodor,” he added solemnly.

The rest of the author’s appearence on Conan was somewhat less controversial. Martin discussed his writing – he is currently at work on The Winds of Winter, the sixth book in the A Song of Ice and Fire series – as well as his childhood and the experience of meeting the actors who play many of his doomed characters. The interview was not without a touch of the macabre though, as Martin did express an uncomfortable amount of glee at the gripping uncertainty and terror which he clearly enjoys inspiring in his fans.

Fans of Game of Thrones can also check out an interview with David Nutter, director of Sunday night’s shocking episode “The Rains of Castamere.”

Game of Thrones season 3, episode 10 “Mhysa” airs Sunday at 9/8c on HBO.