Revelation 9:13-21

The sixth angel blew his trumpet. From the four  horns of the golden altar  that is before God, I heard a voice say to the sixth angel who had the trumpet, “Release the four angels  bound at the great river Euphrates.”  So the four angels who were prepared for the hour, day, month, and year  were released to kill a third  of the human race. The number of mounted troops was two hundred million;  I heard their number. This is how I saw the horses and their riders in the vision: They had breastplates that were fiery red, hyacinth blue, and sulfur yellow. The heads of the horses were like the heads of lions, and from their mouths came fire, smoke, and sulfur.  A third of the human race was killed by these three plagues #— #by the fire, the smoke, and the sulfur that came from their mouths. For the power of the horses is in their mouths and in their tails, because their tails, which resemble snakes, have heads that inflict injury. The rest of the people, who were not killed by these plagues, did not repent of the works of their hands  to stop worshiping demons  and idols of gold, silver, bronze, stone, and wood,  which cannot see, hear, or walk.  And they did not repent of their murders, their sorceries, their sexual immorality, or their thefts.