Revelation 14:18
And another angel came forth out from the altar, he that has authority over the fire; and he called with a great voice to him who had the sharp sickle, saying, "Send forth your sharp sickle, and gather the clusters of the vine of the earth; because her grapes were ripe."
Revelation 16:8
And the fourth poured out his bowl upon the sun; and it was given to it to scorch the men with fire.
Revelation 6:9-10
And, when He opened the fifth seal, I saw, underneath the altar, the souls of those who had been slain because of the word of God, and because of the testimony which they were holding.
Revelation 14:15-16
And another angel came forth out of the Temple, crying with a great voice to Him Who was sitting upon the cloud, "Send forth Thy sickle, and reap; because the hour to reap came, because the harvest of the earth was fully dried.