Feeding Halls for Eldritch Horror

The main attraction of the Feeding Halls is, of course, the Eldritch Horror Itself living at its center, deeply asleep—hopefully for centuries to come! To ensure this, the Halls are permanently watched by teams of powerful mages relaying each other. They're not here to prevent the Horror from escaping—there is very little they could do against this—but to sound the alarm at the slightest sign of unrest on Their part so that the gods can rush to intervene.   Beyond jailing the Horror, the purpose of the Halls is to welcome the rituals necessary to keep It asleep, and those rituals need a vessel. Thus, for one year, the Halls host the next vessel in a "guest room", so that they can be properly prepared and ritually treated before their final sacrifice to the Eldritch Horror.   This vessel is the only actual resident of the Halls. Indeed, the priests responsible for the rituals don't live there themselves but only come to do their job, similarly to the servants assisting them. This is all to avoid anyone staying too long in proximity of the Horror and risking falling under Its influence.

Location

The exact location of the Feeding Halls is a closely guarded secrets known only to the royal archives, the king, and the chief priests of the main gods of the country. In reality, the Halls are not as isolated in the desert as everyone would like to think, and they can be easily reached in a few hours of magically-enhanced travel from the capital.    

Entrance

The Feeding Halls are a massive white marble building bursting out of the desert. They're similar in design to the typical temples to the gods—especially since all the most important buildings in the country have been designed by the architecture god and share her distinctive style. Yet, the Feeding Halls have not for vocation any worship, as illustrated by the fact that there is only one entrance—and exit.   It's located at the top of an imposing staircase located in the center of the south side of the building. The doors are kept opened so long as the sun is in the sky, allowing it—and through it the purifying powers of the sun god Q—to hit the corridors. A system of mirrors inside the building ensures that the light penetrates all corners and chases all shadows. As soon as the sun set, taking with it its protection, the entrance doors are sealed closed.  

Rooms

The inside of the Halls are made of long corridors with extremely high ceilings. All walls and ceilings are build in the same shining white marbles as the rest of the building, but they're also engraved with magical inscriptions that have been filled with a wild variety of metals (gold, platinum, copper, lead etc), all chosen for their specific magical properties and conductance.   The main point of the corridors is to support those inscriptions and the magic they contain which form the seal around the Horror. Thus, the corridors run through the whole building in confusing direction without leading anywhere. Nevertheless, near the entrance, a few doors are available, leading to a guard room, the "guest rooms", and ritual rooms.  

Center

Right at the center of the building, all the corridors converge to a single but massive pair of door that are sealed with magic. Only the presence of one of the major gods from our local gods' council can open them. Few people have the displeasure of being present during such time, but the priests leading the Feeding rituals have reported that beyond the doors is a platform covered in ritual markings and suspended directly above an inscrutable abyss. Anyone not on the menu is warned not to look too closely in there...

The Feeding Halls have always been the target of the enemy gods of our country, as freeing the Horror would swiftly get rid of us. That the rival gods would then have to face the Horror themselves seems to have escaped them...   Yet, this is not my main concern with the Halls. No, even without enemies, the place is super sketchy! The whole building is, of course, under the direct and complete control of the gods, and it is certainly one area where they're not hiding their constant involvements and interest. Despite how isolated the Halls are, there are tons of rumours about what's going on there, reports of people not officially selected as sacrifice nevertheless disappearing from the neighbouring regions, and wild magic outburst escaping from the buildings as a results of mysterious experiments.   While most people dismiss this as tall tales, what I've seen inside the royal archives preclude me from this luxury. It's quite clear the gods are attempting to get rid of the Horror for good—splendid idea! Except that they intend to themselves feed on Its power along the way.   Of course, the gods are the one who captured the Horror in the first place, and the one who go through lots of troubles to keep it where it is. You'd think they could be trusted to know what they're doing. However, working in the archives, I've learned too much about the size of their hubris...