Apocalyptic light novels can also portray the end of the world as a sudden cataclysm. It could be a meteor strike, a powerful demon invasion, or a sudden shift in the magical or technological balance of the world. The characters are then thrust into a world that they no longer recognize. They have to adapt quickly to survive, facing new and terrifying threats. For example, if it's a demon invasion, the characters may have to learn new combat skills and find ways to defend themselves against creatures they never knew existed before.
In many apocalyptic light novels, the end of the world is depicted as a slow decay. Resources are depleted, and society breaks down bit by bit. People struggle to survive in a world that is becoming more and more uninhabitable. There are often conflicts between different groups over the remaining resources. For instance, in some novels, there are tribes or factions that fight each other for food, water, or shelter. The landscape is usually desolate, with cities in ruins and nature taking over in a menacing way.
Apocalyptic light novels often portray the end of the world through various disasters. For example, they might show a world destroyed by magic gone wrong, like in some fantasy - based ones. Or it could be a technological disaster, such as a malfunctioning AI system taking over and causing chaos.