For a while, the theory has been that Tyrion Lannister is the third head of the dragon but Game of Thrones has seemed to abandon that path. However, the books may go through with it. If Tyrion is not the 3rd head in the show… who is?
Books in order
A Game of Thrones (1996)
A Clash of Kings (1998)
A Storm of Swords (2000)
A Feast for Crows (2005)
A Dance with Dragons (2011)
The Winds of Winter (forthcoming)
A Dream of Spring (forthcoming)
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Learn first what a "dragon dream" means and then talk about dragons and dreams.
Tyrion was dreaming of dragons he was NOT having premonitions and prephetic dreams that "dragon dreams" mean.
As for Tywin yes he was the Hand of Aerys but long before Tyrion was born, the timeline does NOT much for Tyrion to be Aerys' child. And yes Tywin told Tyrion "youre not my son" but he also told that to Jaime as well.
Have you actually read the books?
I have a theory about all the Targaryens, by which Tyrion would be one too! It sounds stupid, but all of them kill their wifes with sex/childbirth! Raeghar’s kids birth almost killed Elia, it 100% killed Lyanna, Aerys’s wife died giving birth to Daenerys, and Tywin’s wife died during Tyrion’s birth, and you k ow the rumour about her affair with the mad king. Tyrion fits the bill! Also by this theory, I am affraid Dany is in for some very life threatening child birth
I had posted this question after Tyrion set Rhagal and Visarion free when they were left chained up and we're no eating. It looked to me that Visarion was sniffing Tyrion before he unchained him. I felt Tyrion had to be Targarian because in the book, they burnt the prince of Don when he tried to steal one.
George has stated that someone doesn't necessarily have to be a Targaryen to ride dragons. This does, however, present the loophole of individuals being descended from Targaryens or other Valyrians to ride dragons. So, in the books, my vote for the three heads are Dany (obviously), Jon (also pretty obvious), and Young Griff. I wanted to say one of Oberyn's bastards or maybe Doran's children. Or even one of the Baratheons, Stannis or one of Robert's bastards, though both all three scenarios are highly unlikely. We've just had more setup with Young Griff. It's also possible Varys convinced Aurane Waters to betray Cersei with a promise that he could marry Daenerys, and since he's definitely of Valyrian descent, he might be able to ride dragons as well.
First wow never been first !