The Ordinary Fourth Natural Disaster

The Milky Way in a remote corner has spent 10 billion years peacefully, and is peacefully watching the periodic demise of the fighting children in her arms. Nowadays, another round of young civilizations rises from the cradle of their mother star and looks at the starry sky again, and outsiders who mistakenly enter from outside the fourth wall will bring a slight disturbance to this ordinary cosmic cycle. Just like the year she was born, the story this time also starts with a big explosion...