Oberyn "The Red Viper" Martell

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 "I am a bloodthirsty man, you see. And it is me you must contend with now, not my patient, prudent, and gouty brother"

 

Oberyn aka The Red Viper is another one of my favorite characters of the series. Since he has not been formally introduced in the show yet, I'm going to give some background and also tease what to expect from his story. He is the youngest brother of the current Prince of Dorne, Doran but there is a large age gap between them which can be a cause of contention between the two. Even from his teenage days he was a force to contend with. After being found with the paramour (lover/mistress) of Lord Edgar Yronwood (who had been fostering him),  he was challenged to a duel that was to go until first blood (as tradition). Despite both taking cuts, Edgar's wounds ended up killing him, giving Oberyn the moniker of Red Viper (as those around believed that he used a poisoned weapon). Afterwards he had to live in exile before peace was insured. During this time, he taught himself even more about poisons, traveled to the Free Cities and even went to Oldtown to learn to be a maester before he gave that up from boredom. He was also very close with his sister Elia who was murdered on the orders of Tywin Lannister during the Sack of King's Landing. For this reason, he has hardly left Dorne in the years since that happened and his feelings regarding the Lannisters (and their rule) are currently unknown.

 

Despite the culture/custom of not raising bastards, he took the initiative in raising all 8 of his daughters, known as the Sand Snakes. 4 of his daughters have different mothers with different backgrounds from Westeros and beyond named Obara, Nymeria, Tyene and Sarella. He also has 4 daughters with his paramour Ellaria Sand; Elia, Obella, Dorea and Loreza. The Sand Snakes probably won't appear until season 5 but just know that they have that name for a reason and they are well taught by their father.

 

He is being introduced into the show this season, presumably to attend the wedding of Joffrey and Margaery. Other than that we can not be sure of his motivations, but be sure that he will bring some life (and style) into Kings Landing.