Revelation 9:15-19
9:15 Then the four angels who had been prepared for this hour, day, month, and year were set free to kill a third of humanity.
9:16 The number of soldiers on horseback was two hundred million; I heard their number.
9:17 Now this is what the horses and their riders looked like in my vision: The riders had breastplates that were fiery red, dark blue, and sulfurous yellow in color. The heads of the horses looked like lions’ heads, and fire, smoke, and sulfur came out of their mouths.
9:18 A third of humanity was killed by these three plagues, that is, by the fire, the smoke, and the sulfur that came out of their mouths.
9:19 For the power of the horses resides in their mouths and in their tails, because their tails are like snakes, having heads that inflict injuries.