Dark Magus Returns - Chapter 1741: The Final Battle

I finally managed to kill the demon lord.

This is a story of an ordinary boy gaining unusual powers from his nightmares… It all started when Lin Sheng experienced something strange on what he thought was just another normal day. He begins to have recurring dreams that lead him on an incredible journey of discovery as he encounters spine-chilling monsters and elusive secrets.

- Description from Novelupdates

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

In the era of steam and mystery, becoming a correspondence student at the Thaumatology Academy was something Shad never thought of.

A whispering voice rang in my ears, who was reciting the poems of foreigners——

The old gods and aliens,

When the brassy rings of fate turn,

The golden runes are flickering.

steam surge,

the fire flickers,

Relic echoes,

The old gods revived.

The outstretched hand after the thick fog,

Pull back the hazy curtain of the crazy age.

Guests from afar explore the lands of the Old Continent,

Striking the melody of the next era.

Came here through the gate of time,

Shad put down his suitcase,

Look at the silvery moonlight overhead.

- Description from novelbuddy