Abimelech the son of Jerubbaal went to Shechem to his mother's brothers, and spoke with them, and with all the family of the house of his mother's father, saying,
"Upon one stone"  (Judges 9:5).  This means that all of Gideon's sons, except Jotham who escaped, were executed upon that one rock, used as a block.  This type of wholesale murder was often practiced in antiquity, as in the cases of the seventy sons of Ahab (2 Kings 10:7), the seed royal of Judah (2 Kings 11:1), the whole house of Jeroboam (1 Kings 15:29), and the whole house of Zimri (1 Kings 16:11,12).  Atrocious as such deeds were, they were no more evil than the wholesale murders inflicted upon mankind by the vicious lords of Communism such as Stalin and Castro in this present century, whose murderous "liquidation" of helpless victims reached a total of millions.  No less gargantuan wickedness was that of Adolph Hitler in Nazi Germany.