When the thousand years are ended, Satan will be released from his prison
and will come out to deceive the nations at the four corners of the earth, Gog and Magog, in order to gather them for battle; they are as numerous as the sands of the sea.
They marched up over the breadth of the earth and surrounded the camp of the saints and the beloved city. And fire came down from heaven and consumed them.
References for Revelation 20:9
And the devil who had deceived them was thrown into the lake of fire and sulfur, where the beast and the false prophet were, and they will be tormented day and night forever and ever.