Charles Ellicott Commentary Judges 9:20

"but if not, let fire come out from Abimelech, and devour the men of Shechem, and the house of Millo; and let fire come out from the men of Shechem, and from the house of Millo, and devour Abimelech." — Judges 9:20 (ASV)

Let fire come out. —The malediction is that they would perish by mutual destruction. It was exactly fulfilled (Judges 9:45–49). So when Oroetes was crucified as he had crucified Polycrates, Herodotus notices the similarity of the Nemesis (3:128).