With people here from multiple realities and multiple times, the Apocalypse or Armageddon - or whatever term you might use to describe apocalyptic events - aren't rare. Every culture has tales of them, myth or reality. Out there, someone or more than one person experienced the near or actual end of the world. I've seen it talked about or referenced more than once. Now I'd like to hear the details.
The events don't unnecessarily have to involve the Four Horsemen - anything that was the supposed 'the end of the world as you knew it' counts, especially the near misses and how they were stopped in your times and worlds and universes.