[ArkhanTheBlack]

I'm not sure, I didn't see anything in the event log.
I just saw the impact hit in my capital followed by huge corruption in the area.
My conclusion was that Sss'ra was casting it from Myrror since he declared war a few turns ago.
Though I don't know exactly if it was call the void since I don't know the exact animation anymore. But it was the only spell that could cause such a huge area of corruption. So I assumed it was from Sss'ra.