A living wall begins giving birth to human foetuses, and nursing them.
As they grow older, they have become almost like a tribe of feral humans. They begin raiding nearby settlements and kidnapping villagers to feed to the wall. Pregnant woman are especially valued.
>>54272261
Well, if the theme we're going for is horror/magical realm...
>Demons of gluttony emerge from a "naturally" occurring hellgate, possessing the populace and causing extreme hunger. The infected begin to eat more and more to the point where they bloat to massive sizes and devour anything within reach, including trees, inanimate objects, medium sized animals, and the uninfected. Sometimes they even chew.
>>54272261
I'm in.
The wallmen produce everything they need from the body of the mother wall. Its dead patches of skin become their leather, its teeth their tools and weapons.
Young wallmen are hairless, and unnaturally pink and veiny, but their skin looks more human as they mature. With a wig, a wallman might be able to pass for a feral human... if not for their distinctive, potent odor.
The Grand Cathedral of Beletek, god of justice and mercy, has been the second-tallest building in the empire's capital since memory. The clerics, in their distinctive black and violet robes, have been as long respected as the empire's arbiters of law and charity.
Three months ago, the grand priest was stricken by a mysterious fever, which soon spread to his acolytes.
Two months ago, the cathedral sealed its doors in a quarantine of the clergy, allowing in only those parishioners already infected.
One month ago, the windows of the tallest tower began billowing thick, black smoke. The smog poured ceaselessly, day and night. Occasionally, the sound of bells echoed through the city.
Today, just before dawn, the smoke stopped, and the gates opened. Nobody has come out yet, and nobody has been bold enough to enter.