The second half of Tribulation period (The Great Tribulation)
If the first half of Tribulation will be a difficult time,the second one promises to be the most suffered time for the human kind. That's why the second half is also known as "The Great Tribulation".
Within these last 3.5 years, the antichrist will use the rebuilt temple to declare himself as God. The antichrist will also control the worldwide economy within this period, until he is defeated by Jesus Christ. To do so, the antichrist will put the human kind under his pressure and will demand a mark to swear loyalty to him (the mark of the beast).
Within this period, God will also send the Bowls judgement : the third and last judgement upon earth.