Being a former ninja of Yugakure, the Village Hidden in the Steam, Hidan is the immortal, bad-mouthed partner of Kakuzu. Being a member of the Jashin religion, he worships a deity of the same name, and believes that anything less than death and total chaos is a sin. Hidan's special technique is unique only to him because it requires him to basically kill himself, but since he is immortal he cannot die. He consumes the blood of his enemy, then draws the Jashin's triangular design on the ground. Standing within the triangle he is then linked to his enemy in a voodoo-like sense. Any damage that Hidan receives is then transfered to the opponent, making it quick easy for him to kill.
This technique was explained during his battle with Asuma Sarutobi. Hidan eventually kills Asuma, and then the fight is later continued with Shikamaru avenging Asuma. Hidan is blown apart, and Shikamaru buries his still-speaking remains in a place where no other member of Akatsuki can find.
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