Quran 18:99 — The Cave (Al-Kahf)

At that time, we will let them invade with one another, then the horn will be blown, and we will summon them all together.

[18:98] He said, "This is mercy from my Lord. When the prophecy of my Lord comes to pass, He will cause the dam to crumble. The prophecy of my Lord is truth."

[18:100] We will present Hell, on that day, to the disbelievers.