As Elena and the Azure Legion were getting close to the city of Kamashi, they started to feel some kind of dark presence in the air. But this was not surprising to them as they had already heard about this occurance. The city of Kamashi was actually built in an area where a war between two ancient peak legendary powerhouse had happened.
In that ancient war, almost five million demons had died and their blood gathered together to create a blood pool which was also filled with the grudges of the people who had died here. The peak legendary powerhouse who had won the war became a demigod after the end of the battle and had sealed the blood pool underground.