The series finale of Game of Thrones meant a lot of things to a lot of people, but for author George R.R. Martin, it was the conclusion of an unfathomable journey.

In a new post on his site Not a Blog, Martin recalls when he first met series creators David Benioff and D.B. Weiss for a lunch (“that lasted well past dinner”) and quizzed them on the foreshadowing he’d laid out in the pages of his A Song of Ice and Fire tomes. Who was Jon Snow’s mother? Apparently Benioff and Weiss guessed right, and the rest was history.

“I had no clue, that afternoon at the Palm, that I was about to embark on a journey that would change my life.”

Martin devotes a large chunk of his post-mortem to thanking Benioff, Weiss, writer Bryan Cogman (“the third head of the dragon”), and the cast and crew who brought his world to life. He also assured fans that he was keeping busy and looking towards the future — which includes finally publishing The Winds of Winter, the planned sixth novel in the Song of Ice and Fire series.

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“Winter is coming, I told you, long ago… and so it is,” he writes, expressing remorse for how “late” the book to its intended release. “But it will be done. I won’t say when, I’ve tried that before, only to burn you all and jinx myself… but I will finish it, and then will come A Dream of Spring.”

On top of writing his final two ASOIAF novels, Martin is producing and developing five series at HBO, including the anticipated Game of Thrones prequel series and an adaptation of Nnedi Okorafo’s acclaimed novel Who Fears Death, along with a TV version of Wild Cards at Hulu and another series at The History Channel. He also intends to produce a series of short films, collaborate with Meow Wolf, and possibly work on a video game project.

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But the books remain a priority, and Martin says the final product will differ from where Benioff and Weiss went with the series. We’ll probably see Jon Snow and Daenerys Targaryen come together, clash, then burn down the relics of the past. Tyrion will probably watch his queen go “mad,” before heading to a trial and electing Bran. But there will be nuance, and Martin could change things on the fly as he explores creative possibilities.

I am working in a very different medium than David and Dan, never forget. They had six hours for this final season. I expect these last two books of mine will fill 3000 manuscript pages between them before I’m done… and if more pages and chapters and scenes are needed, I’ll add them. And of course the butterfly effect will be at work as well; those of you who follow this Not A Blog will know that I’ve been talking about that since season one. There are characters who never made it onto the screen at all, and others who died in the show but still live in the books… so if nothing else, the readers will learn what happened to Jeyne Poole, Lady Stoneheart, Penny and her pig, Skahaz Shavepate, Arianne Martell, Darkstar, Victarion Greyjoy, Ser Garlan the Gallant, Aegon VI, and a myriad of other characters both great and small that viewers of the show never had the chance to meet. And yes, there will be unicorns… of a sort…

Martin recently squashed rumors that The Winds of Winter was secretly complete and being held back by HBO until the series adaptation wrapped. Instead, he’s just trying to get the dang thing done. And in the end, he’ll be happy both versions of his epic tale exist.

“Book or show, which will be the “real” ending? It’s a silly question,” Martin writes. “How many children did Scarlett O’Hara have?”

“How about this? I’ll write it. You read it. Then everyone can make up their own mind, and argue about it on the internet.”