According to the lore, what instrument should be used to kill vampires?

As vampire myths spread across Europe, the tools used by hunters became more standardized. The infamous stake, crafted from wood, became a universal weapon against vampires. The belief was that driving a stake through a vampire's heart would destroy it. The origin of this belief is thought to stem from the way decomposition can lead to bloating, and a bloated cadaver’s heart could be knocked out with a wooden stake.

Source: Vampire Killing Kit