Many people maintain that the gods depend on their worshippers for sustenance, and that a god whose cult dies out dies with it. This is a comforting fiction. It allows mortals to believe that they are, at least in aggregate, indispensable.
In truth, the gods endure regardless of whether they are worshipped or not. However, worship civilizes a god. The gods like to be worshipped; it flatters them, and the flavor of sacrifice is savory. In observing the antics of its followers, and in hearing their entreaties (whether or not it chooses to act on them), a god comes to have some empathy for mortal life, and thus typically acts in a fashion which is, if not beneficial to mortals, at least comprehensible.
A god whose cult has died, however, or who has never had worshippers at all, has no such empathy. Fortunately for mortal civilization, gods without followers frequently embark on pursuits beyond mortal understanding and beyond mortal perception; for this reason, a god whose followers have died out may be forgotten and believed to be dead. When a feral god pursues its ineffable ends on the mortal plane, however, it may unleash titanic chaos without even being aware of the consequences. The worshipped gods may be able to contain a feral god’s rampage, but such is not a trivial undertaking even for the gods; many gods will not intercede to protect their worshippers from a feral god’s wrath.
Thus, the sanctuary of Apsada was built. Apsada lies on a remote island far from civilized lands, but all civilized lands send it tribute. Its priests daily offer bountiful sacrifices to … no god in particular. Apsada is, in effect, a lure. The hope is that feral gods will be drawn to the offerings of Apsada, and that the priests there will be able to comprehend them and to worship them. In time, the priests who have built a relationship with a once-feral god will relocate to the mainland, evangelizing and growing the god’s cult.
It is a hard fate to be a priest of Apsada. One may spend one’s life pleading with gods one cannot comprehend or that may not even be listening. One may find oneself consecrated as high priest to a god of murder. From time to time, feral gods fight over the offerings, and Apsada has been obliterated on several occasions by the forces unleashed. Nonetheless, every generation offers up sufficient volunteers, who devote themselves to the task of Apsada so that their homelands may be kept safe from the threat of wild gods.