Revelation 9:9-17

And they had breastplates, as it were breastplates of iron; and the sound of their wings was as the sound of chariots, of many horses rushing to war. And they have tails like unto scorpions, and stings; and in their tails is their power to hurt men five months. They have over them as king the angel of the abyss: his name in Hebrew is Abaddon, and in the Greek tongue he hath the name Apollyon. The first Woe is past: behold, there come yet two Woes hereafter. And the sixth angel sounded, and I heard a voice from the horns of the golden altar which is before God, one saying to the sixth angel that had the trumpet, Loose the four angels that are bound at the great river Euphrates. And the four angels were loosed, that had been prepared for the hour and day and month and year, that they should kill the third part of men. And the number of the armies of the horsemen was twice ten thousand times ten thousand: I heard the number of them. And thus I saw the horses in the vision, and them that sat on them, having breastplates as of fire and of hyacinth and of brimstone: and the heads of the horses are as the heads of lions; and out of their mouths proceedeth fire and smoke and brimstone.