In short, it was definitely Asura who let Grandma go.
Helian Beiming had only heard of Asura in legends. Asura was also a sacrificial soldier, but he was even stronger than one. Asura was obtained by chance: A top-notch golden-masked sacrificial soldier had gone crazy because he was careless in practicing martial arts. After forcefully enduring it, his strength increased by ten times. That was the original Asura.
There were once people who did not hesitate to use medicine to stimulate the sacrificial soldiers to go crazy in order to refine Asura. However, not many of them really survived. Moreover, Asura had a manic personality and was very difficult to control.
Nangong Li's Asura did not look like the rumors. At least, Helian Beiming had never felt any violent aura from him.
Helian Beiming thought of Asura and the three little black eggs sitting in a row on the threshold drinking milk. He looked a little docile.