Lake Of Fire

When the thousand years are over, Satan will be released from his prison and will go out to deceive the nations in the four corners of the earth—Gog and Magog—to gather them for battle. In number they are like the sand on the seashore. They marched across the breadth of the earth and surrounded the camp of God's people, the city he loves. But fire came down from heaven and devoured them. And the devil, who deceived them, was thrown into the lake of burning sulfur, where the beast and the false prophet had been thrown. They will be tormented day and night for ever and ever.

Book Of Revelation 20:01-10

Nothing special, but quite nice sky. Top left cloud looks like beast and bottom part looks like some sort of burning ocean/lava lake.