Arc 8The Basilisk Attack
William learned Nicolas Flamel’s search for the Deathly Hallows, then helped the centaurs fight Voldemort and became entangled in the aftermath of Quirrell’s death. During Ravenclaw’s Quidditch match, a Basilisk attacked Hogwarts, and Dumbledore urged William to use Ravenclaw's Ring to save the dead students, including Harry.
- Nicolas told William how he found the Book of Abraham and traced Salazar Slytherin’s wand through Isolt Sayre, while explaining his search for the Deathly Hallows and his fear of death.
- William spent Christmas with Hermione, gave her a portrait badge, and joined Fred, George, and Cedric to gather Hallucinogenic Mushrooms in the Forbidden Forest.
- William and his friends found Voldemort drinking unicorn blood and fighting the centaurs, and William used a water dragon to battle Voldemort until Dumbledore arrived and drove him away.
- Quirrell tried to reach the Philosopher’s Stone through the enchanted rooms, but Snape’s potion killed him, and Voldemort abandoned his body and turned him into a ghost.
- William confronted Snape over the mushrooms and his accusations, while Dumbledore and Snape discussed Voldemort’s possession of Quirrell and the Ministry investigated William and the events at Hogwarts.
- Hagrid told William that a hooded stranger had given him a Norwegian Ridgeback egg, and Newt agreed to care for it while William prepared for Ravenclaw’s final Quidditch match against Slytherin.
- A giant Basilisk erupted from the Quidditch pitch and attacked the Gryffindor stands, where William struck it with a Conjunctivitis Curse before Dumbledore killed it with the Sword of Gryffindor.
- Dumbledore told William that forty-five students had died, Harry had swallowed the Philosopher’s Stone and died, and Voldemort had unleashed the Basilisk as a distraction, then urged William to use Ravenclaw's Ring to save them.