The Strongest Sage with the Weakest Crest manga volume 21 features story by Shinkoshoto and art by Liver Jam & Popo (Friendly Land).

With the Boseil dungeon monster overflow sorted, Matthias gets down to business creating some jobs for his domain. The long-neglected dungeon may have created a lot of trouble, but it also yields great benefits, allowing Matty to incorporate his passion for resource harvesting and dungeon demolition into a new industry for Boseil. Once known for its delectable cuisine, Boseil will now be known for refining the finest metal ores!