Papa Mert's is an apothecary of the undercity, and serves as both mentor and resource to those who would learn the healing and the poisoning virtues of this substance and that. Its especial concern is the safe gathering and use of flora, and above all of fungi and mosses. It keeps a workroom where a patron may come to know the properties of divers plants, their benefits in medicine and their several dangers alike.
It was Sidra al-Najjar who gathered samples of moss and fungus at Misty Pond and brought them to Papa Mert's to be judged. Upon her arrival she was bidden scrub her hands with "Biyin," a white powder that draws off toxins; and Papa Mert told the several samples apart, setting out their properties and teaching Sidra the safer arts of collection.
More lately the ground about Papa Mert's became the place where the company gave a friendly cat word of the Maiden Tower lead concerning the Crown of Sargon, and pledged themselves to pursue it.