Recaps

Isaac and his allies destroyed Voldemort’s Horcrux in the Lestrange vault during a staged Gringotts robbery that left Karkaroff and the Death Eaters to take the blame. Back at Hogwarts, Isaac learned of the Three-Headed Dog and the Sorcerer’s Stone, advised Percy on writing to Fudge, and received a secret invitation from Sirius.

• Karkaroff, summoned by Voldemort’s Dark Mark, met Snape in London and later rallied former Death Eaters by declaring, “Atoners, assemble!”
• Isaac and Snape joined Vinda Rosier and the Acolytes to plan the Christmas Day operation, then disguised themselves and entered Gringotts during a Death Eater raid.
• Karkaroff and two Death Eaters released a Ukrainian Ironbelly to create a diversion while Isaac’s group used the Imperiused goblin manager to open the Lestrange vault.
• Isaac found Hufflepuff’s Cup, exposed the soul of Tom Riddle inside it, and destroyed the Horcrux with Fiendfyre as Scrimgeour’s Aurors responded to the chaos.
• Karkaroff escaped with two Death Eaters, while Scrimgeour and the Aurors extinguished the Fiendfyre and arrested the goblin manager, and Isaac’s group returned to Hogwarts.
• Snape studied Grindelwald’s history and suspected Isaac was being shaped as a successor, while Isaac told Dumbledore that the Horcrux was destroyed and resolved to look after Harry as a possible counter to Voldemort.
• Harry and Ron told Isaac about the Three-Headed Dog, and Isaac explained that Nicolas Flamel had created the Sorcerer’s Stone and entrusted it to Dumbledore.
• Isaac advised Percy to write to Fudge about the failed Gringotts operation, then received Sirius’s invitation to visit him and agreed to keep his recovery secret from Harry.

As Fudge used Percy’s letter to attack Gringotts, Isaac, Gabriel, and Cedric explored the fourth-floor chamber and cleared its Three-Headed Dog trial. Harry, Ron, and Hermione followed the mystery, while Snape discovered Marcus Flint trapped inside and suspected Isaac’s involvement.

• Fudge used Percy’s criticism of Gringotts to blame the bank for the Diagon Alley disaster, while Isaac spent the Christmas holiday studying alchemy and considering how to bring Sirius Black into the Ministry.
• Gabriel told Isaac and Cedric that Gryffindors had found a Three-Headed Dog in a locked room, and the three Hufflepuffs sneaked there at night.
• After Isaac opened the chamber door, Gabriel, Isaac, and Cedric faced Fluffy, learned that music could calm it, and found Hagrid’s recording awarding Hufflepuff fifty points for clearing the trial.
• The trio found a Trapdoor beneath Fluffy’s bed but chose not to descend, then left Marcus Flint unconscious in the chamber for Snape to retrieve.
• Harry, Ron, and Hermione asked Isaac about the points, and Isaac told them how the chamber’s trial could be cleared and suggested the final prize might be the Sorcerer’s Stone.
• After receiving a note about Flint, Snape went to the chamber, stunned Fluffy, and learned that Flint had been trapped after trying to unlock the door, and Snape suspected Isaac had helped clear the trial.
• Harry, Ron, and Hermione watched Snape leave and concluded that Flint had been trying to clear the chamber’s trials, while Harry continued looking toward Isaac during Herbology.

Isaac led a Hufflepuff group through the fourth-floor challenges, earning points and uncovering a possible future for Hawthorne. Harry, Ron, and Neville opened the chamber too, cleared its first obstacles, and planned to race the Slytherins to the Sorcerer's Stone.

• Isaac told Harry that Snape was not trying to steal the Sorcerer's Stone, but Harry remained unconvinced and planned to investigate with Ron and Hermione.
• Isaac led Cedric, Gabriel, Ernie, Justin, and three older Hufflepuffs past Fluffy and through the plant and flying-key challenges, earning fifty points from Professor Flitwick.
• Isaac's group reached Professor McGonagall's chess challenge, then found Hawthorne making Ernie and Justin run from Fluffy as training.
• Isaac proposed that Hawthorne document how Hagrid controlled Fluffy, which could build Hawthorne's career, and Hawthorne said he needed time to consider it.
• Harry, Ron, and Neville opened the chamber door, lulled Fluffy with music, survived the Devil's Snare, and found Professor Sprout's fifty-point reward behind a Chinese Chomping Cabbage.
• Harry, Ron, and Neville reached the flying-key room, and Gryffindor gained ninety points as news of their success spread through Hogwarts.
• Harry told Isaac how to clear the Herbology challenge, while Isaac warned the trio that the flying keys copied spells and grew faster as their numbers dwindled.
• Isaac told the Hufflepuffs to practice conjuring large chess pieces for the next challenge.

Isaac led the Honey Badger Squad through the final challenges and secured Hufflepuff’s House Cup victory, while Vinda Rosier took the Sorcerer's Stone to Grindelwald. During the holiday break, Isaac helped Percy consider a Ministry career and reunited with Sirius, who wanted to advocate for Werewolves through the Ministry.

• Isaac led the Honey Badger Squad into the fourth-floor Chamber of Secrets, where they overcame Slytherin interference, won a Wizard’s Chess match, brewed the required potion, and passed the Mirror of Erised challenge.
• Isaac retrieved the Sorcerer's Stone from the mirror and tossed it to Vinda Rosier, who took it to Nurmengard for Grindelwald’s followers.
• Hufflepuff won the House Cup with 762 points, and Dumbledore told Isaac that he would advise Fudge at the Ministry and needed a new Defense Against the Dark Arts professor.
• Isaac promised to find candidates for the teaching post, considered Grindelwald’s Acolytes, reunited with Fawkes, and saw the Honey Badger Squad excel in their exams as Hawthorne secured a paid assistant gamekeeper role.
• Isaac advised Percy on Ministry politics and career prospects, explaining Arthur’s authority and helping Percy consider work in the Office of Oddities.
• Sirius invited Isaac and Percy to his home, where he described Arthur’s influence and the Ministry’s treatment of Werewolves.
• Percy rejected a career tied to Fudge and decided to pursue better opportunities and living conditions for Werewolves, while Isaac encouraged him to discuss his plans with Mr. Weasley.
• Sirius revealed that he wanted to join the Ministry and help Lupin, but Isaac said Sirius could not work in the Office of Oddities and noted that something about him was badly wrong.