Oberyn Martell

"Tell your father I'm here - and tell him the Lannisters aren't the only ones who pay their debts."

- Prince Oberyn Martell to Tyrion Lannister

Oberyn Martell is a character that will debut in the fourth season and is portrayed by Pedro Pascal. He's a member of House Martell, the ruling house of Dorne.

Prince Oberyn, known as the Red Viper of Dorne, is the younger brother of Doran Martell, the Prince of Dorne, and the late Elia Martell.

In the books
In the A Song of Ice and Fire novels, Prince Oberyn is the hot-headed younger brother of Prince Doran Martell. He has eight bastard daughters, called the Sand Snakes, the four youngest of which by his current paramour, Ellaria Sand.

Oberyn has a lined face with thin eyebrows, black "viper" eyes and a sharp nose. His hair is lustrous and black with only a few silver streaks and recedes from his brow into a widow's peak.

Oberyn is called "the Red Viper" by friend and foe alike due to his penchant for coating his weapons in lethal poisons, so that even a glancing wound will prove fatal.