Zombie Infestation (e.g. 28 Days Later)
Nuclear/Asteroid Fallout (e.g. Fallout or Lucifer's Hammer)
Alien Invasion (e.g. Battlefield Earth or A Quiet Place)
Global Flood (e.g. Waterworld)
Economic/Social/Technological Collapse (e.g. The Hunger Games or Mad Max)
Killer Robots (e.g. Terminator)
Ruled by A.I. (e.g. The Matrix)
Second Species Takeover (e.g. Planet of the Apes)
New Ice Age (e.g. The Day After Tomorrow)
Other (please comment)