"suddenly they spring Armageddon on you"
Fall of Rebel Angels
Creative Commons Attribution Share AlikeFall of Rebel Angels - Credit: Pieter Breugel

 Armageddon is the place where Good and Evil clash for the last time in the Apocalypse.

Then the sixth angel poured out his bowl on the great river Euphrates, and its water was dried up, so that the way of the kings from the east might be prepared. And I saw three unclean spirits like frogs coming out of the mouth of the dragon, out of the mouth of the beast, and out of the mouth of the false prophet. For they are spirits of demons, performing signs, which go out to the kings of the earth and of the whole world, to gather them to the battle of that great day of God Almighty.

“Behold, I am coming as a thief. Blessed is he who watches, and keeps his garments, lest he walk naked and they see his shame.”

And they gathered them together to the place called in Hebrew, Armageddon. 

Then the seventh angel poured out his bowl into the air, and a loud voice came out of the temple of heaven, from the throne, saying, “It is done!” And there were noises and thunderings and lightnings; and there was a great earthquake, such a mighty and great earthquake as had not occurred since men were on the earth. Now the great city was divided into three parts, and the cities of the nations fell. And great Babylon was remembered before God, to give her the cup of the wine of the fierceness of His wrath. Then every island fled away, and the mountains were not found. And great hail from heaven fell upon men, each hailstone about the weight of a talent. Men blasphemed God because of the plague of the hail, since that plague was exceedingly great.

Revelation 16:12-21