Ji Ning saw the Sword Titan shatter, then saw Autarch Mogg, Autarch Stonerule, Autarch Skyfeeder, and Autarch Titanos all perish in battle. Even he himself was about to die. Ning's heart was filled with resentment and an unwillingness to accept this all. He was filled with remorse towards all the living beings of this Chaosverse, filled with remorse towards his daughter. I'm really sorry, everyone.
He felt resentment, pain, remorse… and boundless hate.
When he saw the maniacally laughing Iyerre, Ning felt true hatred. To use a common saying from his first life in China on Earth, 'even after dying and becoming a ghost, he still wouldn't forgive or spare Iyerre'! However, in his heart he knew that once he died, his truesoul fragments would be completely swallowed and devoured. All that hatred he felt was completely meaningless! It was precisely because he understood this that the hatred and agony in Ning's heart was only further heightened.