Revelation 16:14

16:14 For they are the spirits of the demons performing signs who go out to the kings of the earth to bring them together for the battle that will take place on the great day of God, the All-Powerful.

Revelation 19:19

19:19 Then I saw the beast and the kings of the earth and their armies assembled to do battle with the one who rode the horse and with his army.

Revelation 20:8

20:8 and will go out to deceive the nations at the four corners of the earth, Gog and Magog, to bring them together for the battle. They are as numerous as the grains of sand in the sea.