The Game Of Thrones Vet Who's Playing A New Character On House Of The Dragon Episode 3

The character of Ser Gregor "The Mountain" Clegane was brought to life by three actors over his tenure on "Game of Thrones" — Conan Stevens, Ian Whyte, and Hafþór Júlíus Björnsson — and throughout that time, he killed or maimed countless people. The Mountain was feared by everyone except Cersei Lannister (Lena Headey) and ex-maester Qyburn (Anton Lesser) — the latter of whom had saved him after he was pierced with a poison arrow — and the villainous character will perhaps be most remembered for his brutal murder of the fan-favorite Oberyn Martell (Pedro Pascal), one of the most devastating "Game of Thrones" deaths of all-time. In an interview with NME.com, Pascal said that having his death rank among the most gruesome of the show was fantastic. "If I'm actually up there and if I'm in the top three, I mean then like, everything after is a bit futile," he joked, "It's like, what am I doing? Why am I still trying? I did it."

The Mountain racked up plenty of bloodshed before then, however. One of his earliest on-screen kills happened when he jousted with new knight Ser Hugh of the Vale in Season 1, Episode 4.

Ser Hugh had previously been the former Hand of the King Jon Arryn's (John Standing) squire, and he had been suspiciously promoted after Arryn's death. Unfortunately, Ned Stark (Sean Bean) doesn't get a chance to question Ser Hugh, as The Mountain's lance jabs him in the neck, killing him. After a brief appearance in the following episode, Ser Hugh is gone. 

But not the actor who plays him. Because now, that same performer is playing not one, but two characters in the prequel "House of the Dragon."

While some "Game of Thrones" fans may remember Jefferson Hall's turn as Ser Hugh of the Vale in Season 1, for most viewers, his appearance was too brief. This makes it easy for him to slip into character as "House of the Dragon" twins Tyland and Jason Lannister. 

We first meet this brotherly duo in Episode 3 ("Second of His Name"), beginning with Tyland, a crafty and calculating adviser to the king. He approaches King Viserys Targeryen during Aegon's party, trying to talk to him about the recent events at the Step Stones. Tyland tries to insist it's urgent while Viserys blows him off, more concerned with Rhaenyra's whereabouts.

Later, we see the pair of twins standing together, ready to cheer the arrival of the royal family to celebrate Aegon's name day. Jason's hair is longer and shaggier, distinguishing him from his brother, but we learn this isn't the only distinction between the twins. When "Lord of Casterly Rock" Jason brashly flirts with Rhaenyra Targaryen (Milly Alcock) telling her he'd "do anything for his queen, or lady-wife," we see the same self-assured arrogance that we will eventually come to know in his descendant, Jaimie Lannister (Nikolaj Coster-Waldau).

In George R.R. Martin's books, Tyland had the nickname "The Hooded Hand," and was as conniving as his descendants, manipulating his way from King Viserys' Master of Ships to eventually becoming Hand of the King to Aegon III. It's going to be interesting to see the evolution of the Lannisters in "House of the Dragon."