Warlock of Oceans: My Poseidon System - Chapter 401: Back To The Dungeon

In novels with a stud there is always a Senior Martial Brother like this:

In the early stages of the novel, his innate talent is high, his cultivation is good, his appearance is handsome, and he has an intelligent, cute younger Martial Sister as a fiancée.

In the middle stages of the novel, he is caught unprepared and defeated by a young disciple (the protagonist) in the sect who’s hardly remarkable at all. From then on, he falls from his godly altar and loses his brilliance. Even his young Martial Sister leaves him for someone else.

In the late stages of the novel, he continues to turn dark, going down the Demonic Path and becoming the major villainous boss. However, the protagonist still ruthlessly defeats him and his soul is eternally sealed.

Once Qin Mo opened his eyes, he discovered that he had become this Senior Martial Brother.

- Description from Novelupdates

Failing at the ceremony, Ethan became a Broken Carrier, the worst and weakest of them all.In this world where abilities had to be created and found through the Patterns, Ethan had no choice but to risk everything to change his fate.“So this is my Construct?” Ethan gazed at the massive gears of his core, preparing to harness a new power.The weakest carriers could always become the strongest, all that was needed were methods, desperate and risky, just like the world itself.

She fought in the Battle of Changping and witnessed the killing of hundreds of thousands. She once led the Qin Iron Calvary and battled against the Six Kingdoms. She has seen a third of the land and witnessed the breaking of mountains and rivers. The sound of a grand zither and the light of a great female emperor. A prosperous world that was forged on the battlefield. Yet, these two thousand years are forgotten from history.

- Description from Novelupdates

Gao You transmigrated into a parallel version of the Northern Song Dynasty in Dream of Splendor. At the very beginning, he married Zhao Pan’er in a grand wedding ceremony.“Pan’er, isn’t your husband supposed to be a fool?” Sun Sanniang asked. “How did he manage to enrage Ouyang Xu to the point of smoke coming out of his ears?”“If brother-in-law is a fool, then there are no smart people left in the world!” Song Yinzhan said.“Can a fool write a medical book for the ages? Can he reclaim the Sixteen Prefectures of Yanyun?” Fan Zhongyan asked.“This is clearly the royal son I lost and have now regained!” The Emperor said.