"..Dis is my lucky stake. I have killed many vampires with it. I call it Mr Pointy."The favorite weapon of the vampire slayer, and frequently the only thing capable of finishing them off for good. Because weirdly enough, only wood can kill a vampire, whereas sword impalement (short of beheading) cannot. This may be because the wooden stake was a once living plant, much like the vampire was a once living human, unlike the sword which was never alive. Yes, this occasionally means that someone can be killed via pencil to the heart, or that a bow and arrow can be more effective than a gun. In early vampire fiction, stakes were simply used to pin a "vampire" into its coffin while it slept, keeping it from waking back up and causing trouble. When it became a bizarre all-purpose vampire-killing weapon is unclear.
— Kendra, Buffy the Vampire Slayer