MTL - To Four Thousand Years Later - v6 Chapter 17 secret weapon

Reborn into the world of Yugioh, it's natural if my goal is to become the best duelist!

After dying in an oddly anticlimactic vending machine accident, Kazuki Ren is reincarnated in the demon realm—not as a hero, not as a villain, but as the only human male student enrolled at the mysterious Academy of Ruin, a school where all the professors are demon lords and all the students are powerful, beautiful she-demons.Ren is told he has one task: survive.But there’s a catch. The Academy’s darkest secret is about to awaken, and Ren holds a hidden power that could either destroy the demon world... or rule it.Now surrounded by seductive demons with hidden motives, eldritch tomes, forbidden dungeons, and twisted exams, Ren must master his ability—or be consumed.Magic, mystery, danger, and temptation await in this dark academia harem fantasy.

Having transmigrated to a new world and becoming an ordinary Blacksmith in a Blacksmith Shop, Ye Feng shortly has the Master Blacksmith System activated.

After his divorce, Lu Liang suddenly felt as if he was already half-buried now, after all, he could hear the sound of a revolving lantern, a sign of impending death.But then, he discovered that the noise was actually messages from the future, leading to a dramatic turn in his life....Living in the secular world, we are all ordinary people.Being ordinary isn't too bad; greedy for wealth, lustful, dark-hearted, selfish...[Not a single female lead, enter at your own discretion]