Three Dark Crowns

Three Dark Crowns is a heart-stopping fantasy from Kendare Blake, acclaimed author of Anna Dressed in Blood.
In every generation on the island of Fennbirn, a set of triplets is born: three queens, all equal heirs to the crown and each possessor of a coveted magic. Mirabella is a fierce elemental, able to spark hungry flames or vicious storms at the snap of her fingers. Katharine is a poisoner, one who can ingest the deadliest poisons without so much as a stomach-ache. Arsinoe, a naturalist, is said to have the ability to bloom the reddest rose and control the fiercest of beasts.
But becoming the Queen Crowned isn't solely a matter of royal birth. Each sister has to fight for it. And it's not just a game of win or lose . . . it's life or death. The night the sisters turn sixteen, the battle begins.
The last queen standing gets the crown.