C115 Cave monster

stellar nucleus, the heart of a planet, could be said to be the heart of a planet. A planet only had one stellar nucleus, if a planet lost its stellar nucleus, then this planet would also reach its doomsday.

In this world, every living being, ever since they were born, would have a life ending, including planets. It was just a matter of time. A planet's normal lifespan was 1.2 billion years