Fairy Tail: Lost One - Chapter 14: Twilight Falls, Fiery Retribution

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

The Master of the Tai Yi Sect, Patriarch Xu Yi shattered the void, causing the entire sect to travel through to the interstellar era.

On the deserted planet, the disciples discover a new world:

The eldest senior brother, who specialized in forging, fell in love with mech building. The second senior brother found that alchemy could also be manufactured on an assembly line; The third senior brother fell in love with live broadcasting and was addicted to the Internet; The old Master Xu Yi cracked his whip and urged the disciples, ‘This world is so rich in spiritual energy, how dare you not cultivate properly?’

In the Immortal Cultivation Realm, Junior Sister Sa Sa, who had no spiritual root and powerful spiritual sea, was finally no longer distressed by her inability to cultivate: ‘Mech’s are really powerful!’
Double standard — Xu Yi: … Study it. Isn’t it just mechs, Sa Sa should have one too.

A little bumpkin from a deserted star came to the Federation’s First Academy.

Sa Sa, ‘Wow, the internet is awesome! Mech’s are awesome! Technology is awesome!’
‘You don’t need to cultivate to become strong in the interstellar world, I really love love love it.’

Students from prominent and powerful backgrounds scoffed, ‘Where did the bumpkin come from? Is there something wrong with the admissions system?’
They had no idea that the anchor who exploded onto the internet had a great relationship with the little bumpkin.

Sa Sa: ‘Third Senior Brother is secretly on the internet again!’

The elixir that the little bumpkin usually took and hard to find, the spirit sea boosting pills with no side effects, was actually worth a thousand bucks?

Sa Sa, ‘Second Senior Brother makes the most delicious sweet pills!’

The mech that the little bumpkin casually pulled out was actually the upgraded version of the mech that everyone was fighting over?!

Sa Sa, ‘Eldest Senior Brother will definitely save the best for me!’

The whole planet was abuzz: ‘What kind of divine institution was Tai Yi? How do I get in? Waiting online for a reply!’

- Description from Novelupdates

In a world intertwining magic, knights, and burgeoning technology, young Leonard grapples with memories of a past life in the modern world after waking up reborn in this new, tumultuous reality. Separated from his family amidst a devastating conflict, Leonard's life takes a precarious turn when he is taken under the wing of Alfonso, a reclusive and somewhat deranged wizard. Under Alfonso's tutelage and the rigorous demands of a daily task panel that rewards him for mundane chores with experience points, Leonard finds himself thrust into a harsh survival regime, far removed from his previous life's comforts. His daily life oscillates between mastering arcane spells, learning the delicate art of Earth Ring meditation, and handling the meager sustenance at the prison-like estate where he and Alfonso reside.As Leonard's skills grow, so too does his awareness of the wider conflicts that plague this world, blend of industrial revolution-era technology and dark magical forces. The task panel becomes a strange companion, guiding him through tasks that blend the mundane with the magical, pushing him to grow stronger. Amidst the backdrop of this grim reality. The complex interplay of power, survival, and the echoes of his former life drives Leonard to not only master his new abilities but to unravel the mysteries of this world and perhaps find a way back to his family, despite the cold indifference of his master. Each experience point earned and each new ring formed in his meditation brings him closer to understanding this world's brutal truths and his own place within it.

Lin Ran was transmigrated to a fantasy world and was the top scorer during the martial arts exam.

He was assigned to protect the empress, but because he did not give presents to the general director in charge of the palace affairs, he was demoted to a guard at Mount Sword.

His only job was to clean the swords stored on the mountain.

[You have cleaned the broken sword, Fire Stream. You have been rewarded with 50% proficiency of the Heaven Fire Sword Will.]

[You have cleaned the heavy sword, Dragon Elephant. You have been rewarded with the inner energy of the Dragon and Elephant Divine Art.]

[You have cleaned the demon sword, Dark Wind. You have been rewarded with the Grade 9 method, Phantom Step.]

[You have cleaned the spirit sword, Heaven’s Chance. You have been rewarded with the Eyes that Peek into Heaven.]

“Isn’t this way better than working as the empress’s guard?” Lin Ran quickly decided to remain on the mountain until he had become invincible.

He spent the next 100 years without leaving Mount Sword until the day the barbaric knights from the north invaded the central plains and started to mercilessly slaughter citizens, hoping to break the peace that was obtained through a lot of sacrifices over 100 years ago.

Lin Ran had no choice but to descend from the mountain.