Dungeon Predator - Chapter 520. Empire

A series of short stories in the world of Toaru Majutsu no Index organized into chapters featuring Kanzaki Kaori as the protagonist, going around the world and space doing missions for the Church of Necessary Evil, however, there is more than meets the eye as each incident is connected.

One chapter was bundled with each limited edition release of the Toaru Kagaku no Railgun anime DVD and BDs, with all of them together being equivalent to a single normal Toaru Majutsu no Index volume

One day, Song Shuhang was suddenly added to a chat group with many seniors that suffered from chuuni disease. The people inside the group would call each other ‘Fellow Daoist’ and had all different kinds of titles: Palace Master, Cave Lord, True Monarch, Immortal Master, etc. And even the pet of the founder of the group that had run away from home was called ‘monster dog’. They would talk all day about pill refining, exploring ancient ruins, or share their experience on techniques.

However, after lurking inside the group for a while, he discovered that not all was what it seemed…

- Description from Novelupdates

Apocalypse befell, and roommates performed a skyward ritual.As the fog descended, the Book of Blood Spirit appeared in the hands of all survivors, and only those with a Contract monster could survive.Su Han directed his gaze to the neighbor who had already mutated and twisted, silently pulling out a gleaming fruit knife...Grotesque meat corpses, giant spiders with gaping mouths, eyeballs enveloping the city, one-eyed sharp-toothed hand monsters...Civilization fell, cities shattered, and all humans became meat for the monsters. There was only one way to survive:Use monsters to fight monsters.