C2868 The Reunion of the Grandfather and Grandson

"Childe, you may not be aware, but while we did release six Infernal Demon Kings, three have accompanied the Imperial Majesty to the Ruins of Mountains and Seas. This leaves just us three here to vie for the sigil," the Lord of Equality explained with patience.

This information wasn't exactly classified; the upper echelons of Kaskieso were already in the know