I recommend "God's Advent" to you ~ The protagonist traveled to an era where magic was no longer flourishing. With his talent and knowledge of magic, he climbed to the top of the world bit by bit, desperately shattering the rule of the Martial God and rebuilding the glory of magic. I believe this novel can satisfy your expectations of the "transmigration + magic" theme. If you like it, hurry up and read it! I hope you like my recommendation. Muah ~