My Isekai Life: I Gained a Second Character Class and Became the Strongest Sage in the World! manga volume 4 features story by Shinkoshoto with art by Huuka Kazabana and Ponjea.

Yuji Sano's career has gone from bleak to downright bizarre! Now the world's most powerful Sage, Yuji has joined up with an adventurer's guild and makes quick work of wowing his new allies. And when a dragon arrives to shake the organization to its very foundations, it's up to Yuji to lead the charge.

But even wielding one of the strongest spells in the world, Yuji barely manages to scratch the fearsome beast! Yuji may be the strongest Sage his new world has ever known, but can the Sage best a legendary dragon?!