Elusion of Grand Yore

Publisher's blurb: A svirfneblin clan elder and arcanist of Lumindearth has gone missing. Courageous adventurers have been called upon to bring him home, but they’ll need their wits about them if they are to survive this rescue mission in the enigmatic Underdark. A Four‐Hour Adventure for 5th‐10th Level Characters. This adventure does make use of some supplementary game features from Xanathar's Guide to Everything, so a copy of that book is recommended for DMs planning to run the module.