When you think about it, it's all Xerath's fault.
Existence of Darkins.
If Xerath did not destroy Shurima, Ascended would have someone to guide them. A ruler. Without him/her, they lost their purpose.
Aatrox became the Aatrox because of Xerath. If he knew, I think he would have grudge against him too, maybe even more than Zoe.
Also seems like Ascended assume "the slave" is dead. They are terribly wrong lol.