For the first season in Game of Thrones history, fans and book readers alike have stood on relatively even keel when it comes to the major twists in store, without necessarily feeling that HBO’s version would reflect George R.R. Martin’s unpublished novels. That said, Sunday’s big Hodor twist was apparently two of three major revelations straight from the author’s pen, so what might the final spoiler of Ice and Fire be?

You’re warned of some book and show spoilers alike from here on out, but where showrunners David Benioff and Dan Weiss confirmed that Hodor’s “Hold the Door” origin came straight from a meeting with George R.R. Martin, Entertainment Weekly stepped in to clarify that Hodor marks the second of three major literary spoilers gifted to the HBO drama ahead of time. The first saw Stannis burning Shireen at the stake last season, so where does that leave the third?

According to Benioff, the final major twist “is from the very end.”

Okay! Feels like a lot of ground we could cover there, but it’s at least worth drawing some attention back toward the famed “R + L = J” theory, one the sixth season may be on the verge of confirming, and may not count as one of the three Martin supposedly revealed. After all, legend has it that upon first meeting Benioff and Weiss, Martin would only agree to HBO’s Game of Thrones series if the duo successfully identified Jon Snow’s mother, which they did.

It’s equally likely the final Song of Ice and Fire twist concerns story elements or characters not yet advanced enough (or even introduced) in the current series, whose longevity beyond Season 6 also remains an open question. Still what might we guess as the third literary signpost, and should we take it that all new story points beside the three reveals are of HBO’s making?

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