Who's The Coolest Fictional Assassin Of All Time?

Assassins are deadly and stealthy — so it's no surprise that they have a certain mystique and glamor going on. Science fiction and fantasy are full of assassins who win our admiration while taking lives. But who's the most badass fictional assassin of all time?

Please include a picture, book cover or clip for your chosen assassin. And please mention his/her name and where they appear. Thanks!

Top image: Elektra, from the Daredevil comics.