The first thing Kilorita did was to come straight for him. She left her army in search of him. He couldn't stop her since none of his zombies could fly. This is despite being transcendent.
Even he can't fly. That will require him to interact with the world with his divine sense but the void universe hates him. So he could only watch Kilorita bully her way to the kingdom of spores.
She wanted to use the beheading tactic to end the plague. Unfortunately for her, he could hide very well. The best she was able to achieve was to destroy the fake kingdom of spores in anger before returning.
He said to the Will of the plane from his hiding place, "It is only over when one of us dies."
He can only threaten impotently because he has been checkmated. He surely doesn't have the guts to show his face and fight Kilorita one-on-one. All he can do is increase the frequency of attacks on her city so that she will expend more and more divine energy to protect it.
