"N'Zoth's ability to push the limits of his prison grew, until at least he lured someone in who could break it. He would not have stopped until our entire world was remade in his vision, one of darkness and corruption. I could not let that happen."
So, as Emilia says, he did not stop until N'Zoth was vanquished. Until the corruptor could no longer hurt anyone else, neither the pitiful remnants of his own flight nor the rest of Azeroth's citizens.
no subject
"N'Zoth's ability to push the limits of his prison grew, until at least he lured someone in who could break it. He would not have stopped until our entire world was remade in his vision, one of darkness and corruption. I could not let that happen."
So, as Emilia says, he did not stop until N'Zoth was vanquished. Until the corruptor could no longer hurt anyone else, neither the pitiful remnants of his own flight nor the rest of Azeroth's citizens.