I find the end of the millennium events super exciting.
Revelation 20:7-10 tells us what happens when the thousand years are up. God lets Satan out of prison for one last time to test people right before the final great white throne judgment:
Revelation 20:7-10 (KJV) 7 And when the thousand years are expired, Satan shall be loosed out of his prison, 8 And shall go out to deceive the nations which are in the four quarters of the earth, Gog and Magog, to gather them together to battle: the number of whom [is] as the sand of the sea. 9 And they went up on the breadth of the earth, and compassed the camp of the saints about, and the beloved city: and fire came down from God out of heaven, and devoured them. 10 And the devil that deceived them was cast into the lake of fire and brimstone, where the beast and the false prophet [are], and shall be tormented day and night for ever and ever.
When Satan is loosed for a short season, he goes right on back to fighting against God, trying to deceive people from all over the world. And yet again, some people are just so stubborn in their wickedness that they'll still follow him.
Note: I believe that when the text mentions "Gog and Magog" and “the four quarters of the earth," it isn't talking about the specific war in Ezekiel 38 and 39. Instead, it's just a way of saying everyone outside the Holy City, in every direction from Jerusalem. Keep in mind that this is happening at the very end of the Millennium, so we can’t mix this up with the Gog and Magog mentioned in Ezekiel 38 and 39, which happens before the Millennium. In this case, it just refers to everyone across the earth—East and West—spreading out from Jerusalem to all four corners of the world.
Once Satan has his followers surrounding the saints and the beloved city, Jerusalem, God sends fire down from heaven to destroy them and they‘re sent straight to the lake of fire. Then the devil is thrown in right after them, where he'll stay and suffer forever with the beast and the false prophet.
Satan and all his people are destroyed at the second coming.
2 Thessalonians teaches a lot on what happens at the second coming, as does 1 Thessalonians.
As does the Old Testament teach the fiery destruction of the people of the world on the Day of the Lord.
Malachi 4
“For behold, the day cometh that shall burn as an oven; and all the proud, yea, and all that do wickedly shall be stubble. And the day that cometh shall burn them up,” saith the Lord of hosts, “that it shall leave them neither root nor branch.
2 But unto you that fear My name shall the Sun of Righteousness arise with healing in His wings; and ye shall go forth and grow up as calves from the stall.
3 And ye shall tread down the wicked, for they shall be ashes under the soles of your feet in the day that I shall do this,” saith the Lord of hosts.
4 “Remember ye the Law of Moses, My servant, which I commanded unto him in Horeb for all Israel, with the statutes and judgments.
5 “Behold, I will send you Elijah the prophet before the coming of the great and dreadful day of the Lord.
6 And he shall turn the heart of the fathers to the children, and the heart of the children to their fathers, lest I come and smite the earth with a curse.”
2 thess 1
6 For it is a righteous thing with God to recompense with tribulation those who trouble you;
7 and to you who are troubled, rest with us, when the Lord Jesus shall be revealed from Heaven with His mighty angels,
8 in flaming fire taking vengeance on those who know not God, and who obey not the Gospel of our Lord Jesus Christ.
9 These shall be punished with everlasting destruction from the presence of the Lord and from the glory of His power,
10 when He shall come on that Day to be glorified in His saints and to be admired in all those who believe, because our testimony among you was believed.
2 thess 2
Now we beseech you, brethren, by the coming of our Lord Jesus Christ and by our gathering together unto Him,
2 that ye be not soon shaken in mind or be troubled, neither by spirit, nor by word, nor by letter as if from us that the Day of Christ is at hand.
3 Let no man deceive you by any means, for that Day shall not come, unless there come a falling away first, and that man of sin be revealed, the son of perdition,
4 who opposeth and exalteth himself above all that is called God or that is worshiped, so that he sitteth as God in the temple of God, showing himself to be God.
5 Remember ye not that, when I was yet with you, I told you these things?
6 And now ye know what withholdeth, that he might be revealed in his time.
7 For the mystery of iniquity doth already work: only he who now holdeth back will hold him back, until he is taken out of the way.
8 And then shall that wicked one be revealed, whom the Lord shall consume with the spirit of His mouth, and shall destroy with the brightness of His coming—
9 even him, whose coming is according to the working of Satan, with all power and signs and lying wonders,
10 and with all the deceit of unrighteousness in those who perish, because they received not the love of the truth, that they might be saved.
11 And for this cause God shall send them strong delusion, that they should believe a lie,
12 that they all might be damned who believed not the truth, but had pleasure in unrighteousness.
13 But we are bound to give thanks always to God for you, brethren, beloved of the Lord, because God hath from the beginning chosen you for salvation, through sanctification by the Spirit and belief in the truth,
14 whereunto He called you by our Gospel, for the obtaining of the glory of our Lord Jesus Christ.
15 Therefore, brethren, stand fast and hold to the traditions which ye have been taught, whether by word or our epistle.
16 Now may our Lord Jesus Christ Himself, and God even our Father, who hath loved us and hath given us everlasting consolation and good hope through grace,
17 comfort your hearts and establish you in every good word and work.