Traveling Through Another World: Rebirth of the Great Abyss

[No system, no brainless wisdom] The male protagonist's soul enters the bridal chamber and possesses an idiot young master. In order to live a carefree and happy life with his thirteen-year-old bride, he takes part in the imperial examinations and does business. After everything goes well, he is forced to take sides due to the war and is involved in the internal struggle of the court... In order to protect himself, he makes weapons, practices magical skills, suppresses and recruits rebels, and purges the traitors in the court... And makes an immortal contribution.