Lonely Attack on the Different World (WN) - Chapter 1: (4)

A decision can destroy the sun, moon and stars. A finger can kill the Heavenly Overlord. While chatting, the Heaven and ten worlds can be annihilated.

A poor little kid walks out from a remote mountain area while holding the Nine Dragons and the Incredible Cauldron. With a control over the time and space eternally, he embarks on the Path to God where he defies the odds of the boundless universe gaudily by fighting against royalty and clashing with the legendary generation.

- Description from Novelupdates

Xia Yan passed through to the world of Bleach and became an eleven-year-old boy. He was rescued by Renji and Rukia in the Seireitei, and he was studying at Shin’ō Academy, and he was a student of the same class.
He is a top student of the Shin’ō Academy, and he is vying for strength by various teams. In the end, he has entered the first team of secret mobile maneuvers.
He will use punishment to kill every person who tries to threaten the martyrdom and protect his loved one.

- Description from Novelupdates

Beneath the neon-lit bustling city, unknown monsters lurk.Martial arts sects, biological modifications, cutting-edge mechas, golden bloodlines, abyssal alien species...Chen Feng arrives in this world, similar to Earth, and discovers he can enter a strange dream world where he can pick up various light groups.【Limit-Break Light Group: Can enhance martial arts skills, break limits, and upgrade!】【Attribute Light Group: Can randomly increase four-dimensional attribute points, bigger and stronger, add points!】【Talent Light Group: You gain the talent - Cyan Armor, able to switch combat forms, with power increase by 100%........】【Skill Light Group: You obtain the Extreme Refinement Method, destined to break human limits......】As martial arts gradually decline, and modified humans and cutting-edge mechas flourish,Chen Feng has achieved ultimate limit-breaking in the dream world, integrating extraordinary talents, and continues the path of martial arts!Tear apart mechas with his hands, smash aircraft carriers with his fists!I am the great King of the Century..........My name is Chen Feng, the peak you can never surpass.

I finally managed to kill the demon lord.