An indestructible sword feared and coveted as a weapon of immense destruction. Any sparks struck by its blade ignite fires that cannot be extinguished by means magical or mundane; they burn until they consume all available fuel or else forever.
a black bone
A charred tibia, one end wrapped in wire for a handle, the other chipped to a point. This is an weapon that cannot and should not be; to kill someone with it is to disrupt the natural course of Creation. Anything its victims ought to have done will go unfinished, and the events they would have prevented will now proceed. It can be used to subvert prophecy and kill those protected by destiny, both for good and for bad, but each use weakens the relationship between Cause and Effect just a little more.
la lengua oscura
As we cast shadows, so too does language; in the distant west they call
this speech La Lengua Oscura. Those fluent in it can ponder the
unknowable and devise the impossible; there are kings and queens, now
long dead, who used it to order their subjects to commit unspeakable
acts. True mastery is all but impossible in these latter days, but acquiring basic knowledge has its advantages.
A divine weapon that brings salvation to those it destroys. The Zahir slowly consumes the mind of anyone who sees it, filling them with thoughts of Immanence. When any sentient creature sees the Zahir up close, they must make a Saving Throw vs Magic every day thereafter or lose a point of Intelligence as more and more of their mind dedicates itself to pondering the Zahir. Once their Intelligence reaches 0, they become Lawful and fall into a coma. The Zahir can take any form: it can be a penny, a book, a house.
The Bottom of the City
There ruled a king in distant West, a king for the ages, a king to rival Solomon, a king to shake the firmament. He was Yahya, or El Pastor, or Prestor John, but today his names are not spoken, and his works are cast away. He is just San Serafin now. His 99 Histories record his fall from grace, but each chapter ascribes to him a different sin and a different punishment, so that all must be held in suspicion and none can be trusted. Whether he is dead or asleep or imprisoned at the bottom of his hated, buried city, all of the Histories agree on a single point: anyone who finds him will be granted a single, omnipotent wish, a gift from the Almighty, the power to redeem the world or destroy it.