City of Sin (Yanyu Jiangnan) - Vol 2 Chapter 97: Expedition

Twelve zodiac animals represented the months of the Lunar calendar. No one was aware,however, that these twelve representations were Guardian Gods. These twelve positions were passed down the twelve patron bloodlines. They possessed the ability of the zodiac guardians and silently protected the East.

In the East, the auspicious Qilin, possessing royal blood, descended, reigning over the Twelve Zodiac Guardian Gods, who devote all of their power into protecting the East.

A ruffian Qilin, an Earth that transcends all expectations, a legendary city, and the patronage of the Zodiac animals together create an unforgettable novel.

(Rat, Ox, Tiger, Rabbit, Dragon, Snake, Horse, Ram/Goat, Monkey, Rooster, Dog, Pig)

- Description from Novelupdates

Cha Myung-jun, a sergeant who neared the end of his military service, found himself confined in the Ministry of National Defense’s bas**ent for over three decades due to his newly awakened abilities, just before the outbreak of war. Spending thirty years as the world’s most formidable blacksmith, wielding nothing but hammers, he skillfully outwits the watchful eyes of the Ministry of Defense to serve the war effort and reset the course of time. Now given a second chance at life, can he lead a successful campaign to avert humanity’s downfall and secure its salvation?

In the City of Crime, one law stands above them all: Only the strongest can live.

I became a scientist for an evil organization.…But I’m too competent.