Who killed seventy of his brothers on one stone?
Abimelech
Abimelech ... went unto his father's house at Ophrah, and slew his brethren the sons of Jerubbaal,
being threescore and ten persons, upon one stone: notwithstanding yet Jotham the youngest son of
Jerubbaal was left; for he hid himself.
Judges 9:4