[X] Talk to Yss again, and learn what he found of the promised knowledge (Check previous month's questions: Just where on the scale "Dead/Alive" Vakyrian gods are; Justhow is the 15th connected to the rest of Valyrian Gods; How to best bring a dead Deity to life (and methods of doing so in general); if Yss can do that given a Dragon Orb-worth of power; If it's possible to break the connection the 15th has with the rest of Valyrian Gods, when bringing them back) in his slumber.
-[X] Also sacrifice an appropriate amount of summoned Outsiders (a quick summon/capture of Marilith should suffice) to recharge and expand the pool of charges for Curse-staff.
-[X] Have him try to set up a scrying beacon to the particular Advodaza that seeks to return in Plane Material, using the broken talisman once used to call for it, as a beacon of sorts.
-[X] Ask Yss about the artifact given to you by the Faceless Man. His timeless nature and divinity may be helpful here.