The third day of the competition involves the teams to begin a journey from the Great Volcano, then through the Great Desert, Woodley Bog, and Boggley Wood before camping for the night in Gimmick's Valley. Gimmick uses the Third Crystal on Grubby to make him invisible in order for Grubby to steal some coals for the airship near the Mudblup caves. Gimmick zaps Grubby but not with the Third Crystal but the Fifth. Grubby slurs his speech and the three friends discover that the power of the Fifth Crystal is to increase and decrease objects. Meanwhile, Quellor learns of Tweeg's participation in Wizardweek and sends Drudge, Sludge, and Trudge to collect him. The henchmen catch up with Tweeg on the edge of Woodley Bog. LB convinces them that Tweeg has a fatal contagious disease and frightens them off.