Arianne Martell is another major Martell that will be introduced next season - she's the daughter of Doran and the heir to the throne of Dorne, and thus a future player in the game of thrones. As a child, Arianne found a letter from her father to her younger brother Quentyn, detailing how he would one day rule Dorne. Arianne believed that her father had abandoned her, and this led them to be alienated for many years. Arianne concocts a plot to crown Myrcella as queen of Westeros, thus putting Dorne-backed Myrcella at war with King's Landing-backed Tommen. If Myrcella became queen, she would then install Arianne as princess of Dorne, as is her right. This attempt fails, however, and after she angrily confronts her father, Doran reveals the truth: Arianne wasn't meant to be princess of Dorne because she was in a secret marriage pact with Viserys Targaryen, and she would then go on to be queen of all Westeros when Viserys took the throne. Arianne will likely be a big part of the sections of Season 5 set in Dorne, meaning she'll appear in 8 to even all 10 episodes of the season.
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