Cheng Yan travels through time, only to end up becoming an honorable prince in the Middle Ages of Europe. Yet this world was not quite as simple as he thought. Witches with magical powers abound, and fearsome wars between churches and kingdoms rage throughout the land. Roland, a prince regarded as hopeless by his own father and assigned to the worst fief, spends his time developing a poor and backward town into a strong and modern city, while fighting against his siblings for the throne and absolute control over the kingdom. Join Roland as he befriends and allies with witches and, through fighting and even farming, pushes back invaders from the realm of evil.
"Um..." Sylvie carefully examined the shell and checked it against Roland's design for a long time. She pointed at the detonator and said, "It seems this bronze tube is not aligned with the nail on the top."
"How about the spring?" asked Anna. "Is it still stuck at both sides of the iron pan?"
"One has gone bad."
"To the left or the right?"
Anna asked about every detail, and then wrote all the problems down in a notebook.
After collecting the reasons leading to the failure, they began the next round of test firing, where Summer's playback ability could be used four times. Thus the efficiency of the improvement had become unprecedentedly high.
Unfortunately, the next two rounds of test shooting failed again. Roland had to declare that the testing would continue the next day.