Solo Leveling Novel Volume 3 was written by Chugong.

When Jinwoo gets his rank reevaluated, the results are even better than he could have dreamed of...but more importantly, a chance to heal his mother from her strange illness falls into his lap. In order to find the cure, he must make his way further into the Demon’s Castle—and now that there’s finally hope at the end of the tunnel, nothing can get in his way.