Green Mountain - Chapter 11 - . Little black cat

Protagonist travels between different anime worlds to right wrongs and uncover his reason for being along the way.

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

My name is Joelson, and I traversed across the world. I arrived at a continent of sword and magic and became a noble sorcerer.

The prosperity is about to come to an end, and the poor boy quietly rises.

Traveling across time and space, seek the leader of the world.

- Description from novelbuddy