David slew Goliath with a rock.
“So David prevailed over the Philistine with a sling and with a stone, and smote the Philistine, and slew him; but there was no sword in the hand of David.” (1 Samuel 17:50)
A rock.
Now just a cotton pickin’ minit here. Let’s be fair. He only knocked Goliath down with the rock. Then he used the giant’s own sword to behead him. The rock did not kill him. The sword did.