The Titanic Priesthood is the government of Deo Esari and the custodian of the titan bones buried through the Kelder Mountains, which is the same as saying it holds most of the world's supply of the one material that carries Deoric charge without rotting. Nineteen parts in twenty of all titan bone in trade comes out of ground the priesthood controls.
The keepers of the bones
The order reads the harvest as a sacrament. The titans were the first things Azus made, cosmic and deathless until the Ezz Rift drove them mad, and to cut their remains from the rock is an act the priesthood permits only under rite and only to hands it has consecrated. Bone leaves the mountains by the priesthood's measure or not at all. The quarries are closed to outsiders. A keeper who carries bone out for private sale is a defector, and defectors are hunted down and made an example of.
That is the order as it describes itself, and most of its priests have never had cause to doubt a word of it. The doubt lives in a sealed room.
The seal
Two hundred years ago the priesthood did the thing it has spent the two centuries since burying, and the burying is now the largest fact about it. The full account belongs to the Southern Wasting; the short version is that a harvest crew in the southern foothills cut into a titan that had never finished dying, and what bled out of it killed the south in a single season. The leadership of that day understood what it had loosed. It also understood the choice in front of it. Stand before the confederation and the world and admit the priesthood had poisoned its own land and killed a generation of its own people and could undo none of it. Or seal the cause, and let the disaster pass into the record as a visitation no one could explain.
It sealed the cause. The decision is recorded nowhere a petitioner can reach, but its shape is plain enough from the result: a liability buried under two hundred years of silence, and a silence that has cost the order nothing it was unwilling to pay.
What the silence is worth
The seal did more than spare the priesthood a reckoning. It kept the bone scarce. The southern grounds were close to half of Deo Esari's yield when they emptied, and closing them for good drove the price of titan bone to heights it had never reached, where it has stayed and climbed since. Every year the northern veins run a little thinner and the price climbs a little higher, and every climbing price is the priesthood's. Not every keeper reads that climbing price as a thing to protect: a minority within the order, quiet and not its official voice, has let Myrelin Aelvanor of Lenora understand it would welcome a buyer unbound by confederation price.
So the order keeps the south shut for two reasons and lets the realm see only one. The reason it gives is true: the ground will never be safe to work, and the priesthood will not send keepers to die proving it. The reason it withholds is that to reopen the south at all would force the question of what closed it, and the answer to that question sits in the sealed archive at Thillesari, where the present leadership keeps it the way the leadership before them kept it. The priests below them inherit the closure as doctrine and hold it as reverence. They are not lying. They have simply never been shown the thing they would have to lie about.
The priest who holds the map
Esorin has been shown it. He led the only sanctioned survey of the abandoned south within living memory, walked the dead villages, and came back with the whole of the disaster mapped: where the titan lay breached, and why the poison would never fade. He filed the survey into the sealed archive and said nothing that might unseal it, because he had understood, somewhere in the walking, that the map was worth more closed than open. He has risen since to the office that decides each year how much bone leaves the mountains and at what grade, which is as near as anyone comes to setting the world's price for it. He could end the order's long lie in an afternoon, with the proof already drawn and filed under his own hand. He does not. The lie pays him, and the scarcity it protects is the floor under everything Deo Esari has demanded of the rest of the world for two centuries. His own entry carries the full account, and the one private thing the silence costs him.
What the pressure will do
The thing pressing on all of this is arithmetic. The northern veins are finite and visibly failing, demand has never slackened, and the cost of bone is now high enough that pushing south again is the loudest argument in Deo Esari and a standing temptation to every power that buys from it. The priesthood holds the line and lets the realm believe the reason is caution. The real reason is narrower and worse. No crew can be allowed near the southern grounds, because a crew that worked them would find what Esorin found, and a crew that cut deep enough would open the titan a second time. How long an order can hold a line it cannot explain, against a price that rises every year, is the question the priesthood has no answer to, and the one a campaign can put to it directly.