The stake is the most popular weapon used by Buffy. The stake is struck into the heart of a vampire in order to kill it. The stake cannot be made of any other material besides wood in order to be effective in slaying.
If in a situation and you don't have a stake you can use any other pointed wood object, such as a tree branch, pool stick, pencil , broom, drum stick or broken furniture made out of wood.
A crossbow is a missile weapon of the middle ages used for it's distance range amd ability to pierce armor. The crossbow is much quicker than the stake, but has the same dusting effect.
It has to be handled carefully and skillfully. Buffy put it to good use  against Angel and the Master in season one. Several versions of the crosbow have been used on the show.
Holy water is a type of water blessed by a priest and used for religious purposes. It is usually used to burn or frighten vampires.
Crosses are used to  scare off vampires. They have a similar effect to holy water when it comes in contact with the skin of a vampire, it burns them.
Swords can be used to slay vampires, by cutting their heads off. They also come in hand for slaying other demons and monsters.
Other weapons used are troll hammers, knives, magic, rocket launcher, live human voices, direct sunlight, fire, chains, shovel, letter opener,  wrench, blaster gun, malfunctioning blaster, Tranquilizer gun, Jackal knife (Faith's knife), kitchen knives, the dagon sphere, wooden unicorn (horn as a stake), frying pan, spatula, bat, axes, wrecking ball, staff,  javelin, dagger, plastic stake, ingredients for a bomb, ice skate and there are heaps more.
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