Apocalyptic fiction is a subgenre of science fiction that is concerned with the end of civilization due to a potentially existential catastrophe such as nuclear warfare, pandemic, extraterrestrial attack, impact event, cybernetic revolt, technological singularity, dysgenics, supernatural phenomena, divine judgment, climate change, resource depletion or some other general disaster.
The time frame may be immediately after the catastrophe, focusing on the travails or psychology of survivors, or considerably later, often including the theme that the existence of pre-catastrophe civilization has been forgotten (or mythologized).
For example, Armageddon and Deep Impact are considered disaster films and not apocalyptic fiction because, although Earth or humankind are terribly threatened, in the end they manage to avoid destruction.
With few skills and only her kyūdō bow and an English textbook to accompany her, she sets out on a journey through a dark world of murder and survival.
Ultron eradicates most of humanity using nuclear missiles and gains control of the infinity stones which he uses to destroy many inhabited planets, killing most of life in the universe.