Demon Sword Sect's Undercover - Chapter 4 - 3: Thunderbolt from a Clear Sky

William and his college class are ripped from Earth and thrown into Aethel, a world on the brink of collapse. Everyone gains incredible magical powers – except William. Mocked and underestimated, he’s an outcast among heroes. But William has a secret: an SSS-ranked skill that lets him travel to Aethel’s past. Learning lost magic from ancient masters, he’ll surpass his classmates and become the true savior Aethel needs. But can he overcome the dangers of the past and present to forge his own destiny? While others studied about the first mage, William could go back in time and see the first mage himself! While others dreamed of seeing a dragon, William could go back in time, hatch a legendary dragon egg and turn it into his puppy. While others used common materials to craft their items, William could go back in time and mine materials that weren’t find anywhere in Aethel anymore. Is it unfair? Perhaps, but William was not the type of person to not use the powers the universe gave him.

Master martial artists were beings that no one can obstruct. A martial arts expert has been reborn into the body of a genius whose cultivation has been abolished and has been abandoned by a woman. Therefore, he starts cultivating the art of Xing Yi Quan, producing a solar system within his dantian. His innate talent tramples over all the geniuses, and even the geniuses among geniuses.

His powerful spirit and ruthless and ambitious nature, no matter who he is reborn into, will never change! Slaughter is instinctive, being cold-blooded is his personality, exterminating an entire family is only a means towards a goal, cruelty means infamy, and chasing after women… is just an interest.

- Description from Novelupdates

A wicked mother one day brought home a girl. The child was the hidden legitimate daughter of the duke, the heroine of [The Duke’s House Has Three Sons and One Daughter] Loretta. I was Melody, the villainous girl who tormented her and was condemned along with my mother. Not wanting to die like that, I decided to start treating her well now. I personally fed Loretta, put her to bed, and played with her. And then her reaction was…? “I want Melody to marry me!” Caught off guard by her endless affection, I too ended up entering the duke’s family, “I’ll stick right by Miss Melody’s side.” And there, it seems I’ve met a young lord who’s an even bigger ‘Melody fool’? All I did was be kind to survive, but why am I being loved…?!

Three Emperors have died in quick succession. The prince whom nobody had taken notice of unexpectedly succeeds to the throne. He is quickly plunged into layers upon layers of danger. The Empress Dowager dislikes him, wishing to install a younger, more obedient Emperor. His half-brother dislikes him, accusing him of stealing the throne that is rightfully his. The palace attendants and servants dislike him, believing that he is not a true Emperor. The Child Emperor must save himself.