Although this is just a story leak and should be taken with a grain of salt, it does go hand-in-hand with what Tribbie revealed at the end of HSR 3.1 mission. Image Credit: Hoyoverse/Honkai Star Rail.

In the HSR 3.1 mission, we further get clarification that the black cloaked warrior, Flame Reaver of the Deep Dark, was also responsible for the destruction of Aedes Elysiae and the murder of Cyrene.