The main character loves the MMORPG game called Dungeon Explorer Chronicle (Dun-Ex). During one particular day, a beta test event was announced, and he managed to beat it. In exchange for clearing the event, he was granted permission to try the beta test server. Forcing to choose different avatar and skill as the system doesn’t allow his own, he eventually settled on random. However, he is transferred to a place where, as expected, he finds a fat, villainous mob character…! — **The manga has been on hiatus since the publication of Chapter 90 on October 21, 2025, after the adaptation caught up with the source novel. Shueisha announced that the hiatus would continue for the time being until sufficient source material becomes available.**