"Normally, Chaldea ensures the safety of human history for the next hundred years, but in 2015, which is our time, the Near-Future Observation Lens, Sheba, observed that humanity would go extinct in 2016. To clarify this reason and avoid this situation, Chaldea decided to execute the sixth experiment, which was still in the experimental stage..."
After all, having come this far, the girl who served as humanity's last Master was no longer naive and could certainly handle things on her own.
Once she calmed down, she explained everything she knew, including how Chaldea discovered the situation, understood it, and what efforts were made in response.
The sixth experiment still in the trial stage was the Spiritual Particle Transfer technology, which is time travel back to the past. It involved transferring a technician's spirit particles back in time, intervening in events, searching for the singularities, uncovering the truth, or conducting a forbidden ritual of destruction.
