Arc 23World Cup Chaos
William and his friends survived a fire, a monster attack, and a hostage crisis at the Quidditch World Cup, while William rescued the captives and helped Ireland win the final. The arc ended with Professor Babbling reporting that Tom might be in Britain and William confronting Lucius Malfoy over his debts.
- William saved Slughorn from Sanguini, then learned that Barty Crouch Jr. had escaped after setting fire to Crouch's tent.
- William and Hermione investigated the disappearances, found Astoria in Crouch's tent, and warned Fudge that someone might be missing from the campsite.
- William hosted Phoebe and Gabrielle, helped Daphne search for Astoria, and prepared for trouble during the World Cup final.
- William advertised Akali’s Mystery Shop with a Fiendfyre display as Ireland defeated Bulgaria and won the championship.
- Masked wizards and magical creatures attacked the campsite, and William rescued people while fighting Inferi and the Selma Lake Monster.
- A disembodied voice announced that Krum and other wizards were hostages and demanded the release of Bellatrix, Rodolphus, and Rabastan from Azkaban.
- William found Barty Crouch Jr. and rescued the hostages, including Harry, Ron, Malfoy, and Krum, before Crouch Jr. escaped.
- Professor Babbling told William that Tom might be in Britain, and William later confronted Lucius Malfoy at Gringotts over his unpaid debt.