How Does Volume 4 Change The Worldbuilding In Mushoku Tensei?

A new world with nearly unlimited possibilities. A system, classes, magic, skills and monsters. Sounds exciting? But for Jin it didn't go quite as he expected nor was there a princess or a Goddess to welcome him to this new world, his only hope was the system he received. Left alone in the darkness, How will he survive when he wasn't human in the first place?

A witch who has lived for thousands of years has grown bored with her own life and decided to leave it. Since she is an immortal, her soul cannot leave the world. However, what she can do is transfer her soul to another body. By a stroke of luck, she happens to enter the body of a princess. She was considered a miracle because when the Empress gave birth to her, the princess instantly died, along with the Empress. What the witch didn't know was that she has entered such a predicament. She has to endure the love of the cruel Emperor and possessiveness of the crazy twin princes! What will her life be at the hands of such a loving family? In addition, it seems that this body contains mana that was lost in the royal family centuries ago!

Evy was a simple-minded girl. If there's work she's there. Evy is a known workaholic. She works day and night, dedicating each of her waking hours to her jobs and making sure that she reaches the deadline. On the day of her birthday, her body gave up and she died alone from exhaustion. Upon receiving the chance of a new life, she was reincarnated as the daughter of the Duke of Polvaros and acquired the prose of living a comfortable life ahead of her. Only she doesn't want that. She wants to work. Even if it's being a maid, a hired killer, or an adventurer. She will do it. The only thing wrong with Evy is that she has no concept of reincarnation or being isekaid. In her head, she was kidnapped to a faraway land… stranded in a place far away from Japan. So she has to learn things as she goes with as little knowledge as anyone else. Having no sense of ever knowing that she was living in fantasy nor knowing the destruction that lies ahead in the future. Evy will do her best to live the life she wanted and surprise a couple of people on the way. Unbeknownst to her, all her actions will make a ripple. Whether they be for the better or worse.... Evy has no clue.

Al, was thrown into another world for no apparent reason. A new world filled with magical things. However, this wasn't the first time he had been reincarnated. He thought he was just an ordinary youth, but it turned out that his identity was so extraordinary in his first reincarnation. There were his harems still waiting for his arrival. Will he meet them soon and what will happen?

What is fate? Is it something that was destined to happen? Can it be changed? No. If it can be changed, it would't be known as fate, isn't it? They say that fate can be control in our hands. Then, is it possible to take everything in total control in my hands?, I wondered. No, whatever the results is, I'm sure this was fated to happen under my control. This world... will surely go along with my favor. ................ "PLEASE!!! I BEG OF YOU!!! Join the Imperial Knights Academy as a special student or else I will be fired!!!" With such a line thrown to him, the 16-year-old human, Lucifer Nightwalker von Nightmare, an orphan who was stranded on an island with her little sister and magical pet-- was forced to compromise and attend the famous Imperial Knights Academy as a special student. While spending 3 years in the academy, he would meet his fated ones. After he graduates, he would then become an adventurer to explore the world, unlocking the secrets behind. This, will be the starting of his journey. In a world of sci-fi and fantasy. Humans, beast-kins, dragons, vampires, elves, fairies, spirits, dyrads, archangels, demons, dwarves, magical beasts, and much more, co-exist. Which later then, he would become a king-- leading everyone to challenge against the Celestial Gods. However, that was the boy's fate. ...................................... Everything begins with that fateful meeting six years ago. His fateful meeting with the principal of The Imperial Knights Academy. Yet, it wasn't even the beginning of fate. .....................................

Feng Shaotian was a simple guy who desires nothing but peace. Even though his life wasn't that great after the death of his parents. The only comfort he got was the existence of his loyal dog, Ding Bang. He tried to take his life by jumping on the highest bridge in their place but Ding Bang stopped him. As long as he tried to commit suicide, Ding Bang was always there to stop him. Out of sympathy to his dog, he decided to stop commiting suicidal acts. Unfortunately, it wasn't enough. He found no purpose in living, everything felt empty as if something was missing. One day, he finally decided to do something he kept on hold for months for his dog's sake. Suicide... But it was wishful thinking, just as he laid in his bed for his last sleep. A phenomenon happens that change his life. Something magical that only happens in novels. A transmigration to another world. But what will he do when he found out that this place is full of bloody fights? A place where the strong preys the weak. Will the peace lover from earth be able to survive this insane place? Or die like a mob in wilderness?