The fact that only those who were harmed by zombies turned into zombies acted as a smoke screen to hide how they infect others. So the gods thought the zombies were spreading the disease through contact, bites, and attacks but the disease was airborne all along.
The fact that new zombies only appeared in areas attacked by zombies muddled their investigation further and granted the inhabitants a false sense of safety. They put quarantines in place but it didn't stop the appearance of the zombie disease.
The disease spread so quickly that a council meeting of the gods was called. It wasn't a physical meeting. They are communicating using a rune of communication from the god of knowledge and understanding as a relay to connect all of them. No one wanted to meet physically for fear of transmitting the disease.
The Celestial of Knowledge said, "I suspect that one of the gods is causing this calamity. I have made some investigation but I have found no natural means. That means one of you is responsible for this."
As the god of knowledge, he is very familiar with most diseases and plagues. He can even simulate control over them with his knowledge and understanding of them. Even the great gods of diseases and plagues are not as familiar as him with diseases and plagues. But he couldn't find the cause of the plague. All he found after inspecting the zombies was that their bodies were breaking apart and decaying.
Another Celestial asked, "Who is responsible for it then? Surely you must have found the culprit through the divine energy traces."
"I don't know." The Celestial of knowledge replied.
"What do you mean by you don't know? If it is not natural, then it must be divine. If it is divine, then there must be divine energy traces. If there are divine energy traces then there must be a divine source. If you identify the divine source then you have identified the source of the plague. This is common sense. So how can you not know the god responsible for the disease?"
The Celestial of Knowledge became agitated. "I don't know because there are no divine energy traces."
His declaration caused an uproar among the gods.
Another Celestial asked angrily, "Why would you suspect one of the gods of there is no divine energy trace? I hope you were not making baseless accusations."
The Celestial of Knowledge replied confidently, "There are two options for the lack of divine traces. The first one is that this is a natural plague that can't be traced or identified at all. The second one is that this is a divine plague caused by a god who is very adept at hiding their traces. I chose to go with the second option because gods are dying to this plague. No natural plague can affect gods."
"The plague has led to the death of many gods and their godhoods are nowhere to be found. Only a god can kill another god. And only living things will be after their godhood. If it is a natural plague, then this is a terrifying plague that can kill gods. Which option would you rather believe? A sneaky perpetrator or a terrifying natural disease?"
His question was answered with silence. It is the silence filled with dread and fear. Neither of the two options is good. There is either a god killing them silently with a disease or a natural disease strong enough to kill gods.
They don't know which is better or what to do. But one thing is clear, if a god is responsible then there is hope of stopping the plague. They just need to find who among them is responsible for it.
The Celestial of War broke the silence. "If it this disease is caused by a god then there is no reason to worry. Only the weak gods will die. No Celestial has died yet so we are sure that this god can't kill Celestials. This plague will end soon. My point still stands even if it is caused by a natural disease. We Celestials have nothing to worry about."
The Celestial of Knowledge refuted. "That is the situation now. What if the god becomes a Celestial? What if the disease mutates after devouring so many godhoods and becomes capable of killing Celestials too? What do we do then? All we know now is that the disease needs contact and bites to spread. But what if that changes?"
The Celestial of War maintained his stance, "It will only kill the weak. I don't have anything to worry about because I am not weak."
Another Celestial suggested. "Anyway, if it is the work of a god, then I suspect the gods with the domain of plagues and diseases. Only they are capable of such a thing. And the culprit might have the help of a Celestial to hide their divine energy traces for even you to be unable to sense the divine traces."
"What if we got this wrong and it is actually both of the options? What if the disease started as a natural disease but then became a god? This will explain why it doesn't need to use its domain to infect and why it is powerful enough to kill gods."
"There have been no gods in recent times so that theory cannot be true. If you ask me, I think this is a conspiracy by some gods to farm a large amount of faith."
"It could also be for creating a terrifying impression on the inhabitants of the plane for the creation of a domain or the ascension of a grand god into Celestials."
They began arguing about what to do and pointing fingers. They didn't stop until the Celestial Supreme intervened.
The Celestial Of Lightning first ordered, "Silence."
Then she said, "I think this is more than it seems. Something happened 10 years ago. A child of the plane was chosen. And on that same day, Malekite died."