I Became the Villain's Trainer - Chapter 41

Crossing to One Piece world, he became Roger’s younger brother.

Dimensional Rifts permeate throughout the Chaotic Universe, bringing with them immense dangers… as well as innumerable treasures.

In a small Realm, a destitute boy awakens the Idle Gaming System.

Countless Dimensional Rifts later, he lazily raises his head to realize… he is invincible!

On modern-day Earth, An Lin seems to have been abandoned by God.
When his father suddenly disappears, An Lin is left with his father’s immense debt, putting his life at risk.
After being forced to a rooftop by his pursuing creditors, An Lin is unexpectedly swept off his feet and brought to the ground safely.

After learning that he was saved by an Immortal, An Lin is gifted, seemingly out of pure generosity, the ‘God Of War System,’ and a pass to a new realm.
Follow An Lin as he experiences a whole new world of legends, meets many new friends, acquires legendary weapons and tools, and starts on his path of becoming a powerful cultivator. There is never a dull time in An Lin’s new life with his ‘great’ new system!

- Description from Novelupdates