Revelation 16:13-16

13And I saw three loathsome spirits like frogs, leaping from the mouth of the dragon (Satan) and from the mouth of the beast (Antichrist, dictator) and from the mouth of the false prophet;

14for they are [actually] the spirits of demons, performing [miraculous] signs. And they go out to the kings of the entire inhabited earth, to gather them together for the war of the great day of God, the Almighty.

15(“Behold, I am coming like a thief. Blessed is he who stays awake and who keeps his clothes [that is, stays spiritually ready for the Lord’s return], so that he will not be naked—spiritually unprepared—and men will not see his shame.”)

16And they (demons) gathered the kings and armies of the world together at the place which in Hebrew is called Har-Magedon (Armageddon).