Tensei Mae no Tutorial de Isekai Saikyou ni Narimashita. Junbi shisugite Dai-2 no Jinsei wa Easy Mode desu!

One day, a 33-year-old man who spent all his time playing video games to escape reality from an unreasonable life of bullying and power harassment died. However, he was chosen as a candidate for reincarnation to another world, but the woman who guided him to his reincarnation told him that she would not give him any cheats. Instead of cheats, he was offered three months of training at an otherworldly reincarnation training facility. The training facility was supposed to make it relatively easy to acquire skills, but what would he accomplish in three short months? He was given an Appraisal and an Item Box as bonus skills, but he was thrown into the training facility before he could even begin to set up his prowess. He spent three months in the training facility, desperately training to survive his new life. But after 3 months, after 1 year, after 10 years, he was not reincarnated. He was worried he might have gone to the infinite hell of the game world since he died from playing too much video games, but he still trained desperately. In fact, he never thought that the reincarnation process was not completed due to a mistake made by the female guide. After all, when 15 years of training had passed, the information about reincarnation came unexpectedly. The man who had already become a cheat bastard to the point of killing an ancient dragon was trying his best to enjoy the other world in a normal way. (Source: Novel Updates)