There will be a mass disapperance of people. Specifically, all true Christians will be removed from the Earth. It may be attributed to aliens, war, disaster, a combination of these, or something entirely different. But understand that when people are suddenly missing, it was the Rapture. This will be one of the greatest signs pointing to Christ's return. It will happen at least 7 years before His return and will cause many who have heard of this event to come to faith in Jesus.

An antichrist, the beast, will arise. He may just be a man or something a bit more but he will be the answer the unsaved world is looking for. He will play a role in either establishing or enforcing a covenant or agreement between Israel and other nations. This agreement will be for 7 years and in the middle of those 7 years he will declare himself to be god. There will also be a mark that he causes every person in the world to receive. This mark will doom the one who receives it to never ending torment and punishment in hell. Don't trust that man. Don't take his mark. I believe it will have a DNA related component which makes it permanent.

There will be a period of peace of uncertain duration or at least a significant push for peace. This period of time may immediately preceed conflict or follow it or, possibly, start before but reach its full potential after. The world will be united in its missions, values, goals, and efforts. The world will be of one mind and united under the direction and governance of one man, the antichrist. 

There will be hyperinflation, wars, famine, disease, devastation, destruction, and death on a massive scale. There will also be severe climate changes or anomalies that spur great devestation likely through hurricanes / typhoons, earthquakes, volcanic eruptions, and other natural disasters.

There will be impacts to the Earth from objects outside the Earth. This could include meteors, asteroids, or other space debris.

The final and greatest sign that the history of man's rule over this world is ending will be the sign of the Son of Man Himself. The sign will literally be the Son. It is then that Jesus will return to the Earth and set up His kingdom.