Death March kara Hajimaru Isekai Kyusoukyoku (WN) - Book 13 - SS: The Phantom Underground Empire

Waking up from a deep sleep, Lin Yue found herself having transmigrated into a peasant's new wife, and to make matters more complicated, she was a replacement for a deceased wife. The husband, over a decade older than her, had already lost two former wives. It wasn't so much a marriage; she had been sold to the family by her unscrupulous parents. Her fate was out of her hands. Before her stood one, two, three, four children, like a line of burdens, all gazing at her with blurry and hopeful eyes. Lin Yue felt an enormous pressure, “Thanks to Yuewen Book Review Group for providing review support!”

Always looked down upon by others, Ji Feng gains technology far more advanced than the present, as he discovers its abilities, he begins to walk a path far from ordinary. With X-ray vision allowing his to find jade stones in rocks. With this futuristic technology, Ji Feng accomplishes something no-one can compare to. This is the beginning of a legend.

- Description from Novelupdates

SLASH!(So this is death?!!)I, Elysia, found myself dead before even reaching the Demon King's lair, and our Hero Party was completely annihilated.And this was done by none other than a fellow human—my former classmate.He had been mostly invisible during our time at the academy, but then he started committing one crime after another until he became a lackey of the Demon King.Who would have thought that the strongest party of humanity would be wiped out by humanity’s traitors?(If I could go back to the past, I swear I will kill you!)Just when I thought I could finally pass on, I opened my eyes.Five years back, when I first enrolled at Arcadia Academy.And there he was, the traitorous bastard of humanity...****“Huh? Where am I?”One day, I opened my eyes to find myself in an unfamiliar place and came to realize this was the world within the novel Savior's Dawn that I had read.Everything seemed to be proceeding the same as in the novel—except for one thing.The main heroine is glaring at me as though she wants to kill me.Could I survive with the main heroine after my life?

Sherlock is a new generation Dungeon Lord whose ambition is to become the greatest Devil King and building up the greatest Dungeon in the Underworld.