Chapter Summaries

Yinsen left after helping restore Lupin, while Dumbledore and McGonagall speculated that Yinsen and Scáthach might be legendary figures. Later, Dumbledore encountered Yinsen studying the Time-Turner and heard how he hoped to use its principles to connect with the flow of time in other worlds.

• Yinsen thanked Dumbledore, took a feather from Fawkes, and left the room.
• McGonagall questioned Yinsen’s identity, and Dumbledore suggested that Scáthach’s name and abilities pointed to an ancient legend.
• Dumbledore and McGonagall considered whether Yinsen was a legendary sage or a descendant of Merlin, then discussed whether he could help with Voldemort and the Wizarding World’s political troubles.
• Dumbledore wandered Hogwarts, still uncertain whether Voldemort’s return would make matters better or worse.
• Dumbledore found Yinsen experimenting with the Time-Turner, which Yinsen had learned only worked with this world’s River of Time.
• Yinsen explained that he wanted to understand how the Time-Turner connected to the River of Time so he could attempt similar work in other worlds.

Yinsen and Dumbledore agreed to let Voldemort return while protecting Hogwarts, hoping to use the conflict to confront the Wizarding World’s hidden extremists. After Peter Pettigrew and many Death Eaters escaped Azkaban, Dumbledore learned Voldemort’s return was drawing closer, likely during the Triwizard Tournament.

• Dumbledore asked Yinsen what he thought of Tom Riddle and admitted he feared Voldemort’s return would cause innocent casualties.
• Yinsen offered to help Dumbledore protect their friends, and they agreed Voldemort could return while Yinsen guaranteed no one at Hogwarts would be harmed.
• Dumbledore contacted the Order of the Phoenix, whose members chose to remain and face the coming conflict.
• Peter Pettigrew escaped Azkaban, and Dumbledore persuaded Minister Fudge to inspect the prison.
• The inspection revealed that nearly half the imprisoned Death Eaters had escaped, leaving Fudge under pressure to explain the breach.
• Dumbledore asked Yinsen when Voldemort would return, and Yinsen predicted the Death Eaters would act during the Triwizard Tournament.

As Dumbledore prepared for Voldemort’s likely attempt to use the Triwizard Tournament to reach Harry, Harry agonized over whether to leave the Dursleys and live with Sirius. Hermione appeared beside Harry, Ron, and Yinsen with a temporal ripple, which Yinsen harnessed to reverse the chess game.

• Dumbledore and Yinsen reasoned that Voldemort would use the Triwizard Tournament to send Harry to him, so Dumbledore began preparing safeguards for the contestants.
• The professors’ preparations loosened supervision, while Harry helped Gryffindor win the Quidditch Match and Sirius visited him as his godfather.
• Harry told Ron and Yinsen he was unsure whether to leave the Dursleys for Sirius, and Yinsen urged him to decide for himself.
• Hermione suddenly appeared beside the chessboard, and Yinsen sensed a temporal fluctuation around her.
• Yinsen caught the ripple with his magic and made the chess pieces replay the previous game in reverse.

Yinsen realized that each object had its own river of time and began investigating how to manipulate it, though his first uncontrolled attempt left him dizzy. Logan told him he planned to leave Hogwarts after the semester, while Yinsen intended to stay through the Triwizard Tournament and deal with Voldemort before returning.

• Yinsen accidentally caused the chess pieces to replay their past through temporal fluctuations from Hermione’s Time-Turner, then recovered from the resulting dizziness.
• Logan told Yinsen that he planned to use the potion to remove its lingering effects and leave Hogwarts after the semester ended.
• Yinsen said he would remain through the Triwizard Tournament, when Voldemort would return, and could handle Voldemort himself.
• Hermione confronted Yinsen about knowing she had a Time-Turner, and he showed her an identical one of his own.
• Yinsen warned Hermione not to use her Time-Turner recklessly and told her he was studying how it controlled the power of time.

Yinsen advanced his research into time magic, demonstrating that he could manipulate an apple along its Timeline, though the experiment nearly destabilized the spell and erased the fruit. Dumbledore asked him to represent Hogwarts in the Triwizard Tournament, and Yinsen questioned whether he was old enough to compete.

• Hermione questioned Yinsen's research into time, but he argued that the Time-Turner proved time could be studied and used.
• Yinsen excelled in his studies, while Dumbledore stopped professors from placing him in advanced classes because he was still too young.
• Yinsen used time magic in Snape's laboratory to move an apple through stages of its Timeline, then suppressed the unstable spell before it caused a disaster.
• Yinsen told Dumbledore that the apple had been erased from the Timeline and explained how his research combined insights from the Time-Turner and the Time Stone.
• Yinsen considered changing the past to deal with Voldemort but decided it would not improve the Wizarding World's situation.
• Dumbledore asked Yinsen to represent Hogwarts in the Triwizard Tournament, and Yinsen asked whether he was old enough.

Dumbledore recruited Yinsen to compete in the Triwizard Tournament so he could protect Harry from the Death Eaters’ plot. After agreeing to Sirius’s request to prove he could keep Harry safe, Yinsen began their meeting by magically turning Sirius into a sheep.

• Dumbledore explained that Yinsen needed to enter the tournament to protect Harry at close range, and Yinsen agreed.
• Yinsen realized Sirius wanted to test his strength, and Dumbledore asked him not to hurt Harry’s godfather.
• Dumbledore, Snape, and Yinsen met Sirius in a secluded Hogwarts classroom, with Lupin and McGonagall nearby.
• Sirius drew his wand and introduced himself, while Lupin warned him that Yinsen could use Wandless Magic.
• Yinsen brought up Sirius’s Animagus form, then magically took control of him and made him bleat like a sheep.

Yinsen defeated Sirius with a Sheep Transformation Spell and trapped everyone in a space he had created, demonstrating his overwhelming power. Sirius conceded and apologized, and Yinsen assured him that Harry would be safe.

• Yinsen transformed Sirius into a sheep, then created a prairie inside a separate space while Sirius ate the magical grass.
• Sirius returned to normal, spat out the grass, and conceded after learning Yinsen could also turn him into a pig.
• Yinsen reclaimed the prairie and broke the sealed space, revealing that they had remained within Hogwarts.
• Sirius accepted Yinsen's strength, apologized to him, and stopped doubting Lupin's account.
• Yinsen promised Sirius that Harry would never come to harm.

Yinsen discussed the Quidditch World Cup and summer plans with Hermione, then asked his companions whether they wanted to continue at Hogwarts. He left their choices open, and they decided who would stay for the coming school year and beyond.

• Hermione asked Yinsen whether he would attend the Quidditch World Cup, and he said he had little interest in Quidditch.
• Yinsen told Hermione that he had rejected the Slytherin Quidditch Team after beating the entire team in a challenge.
• Hermione considered spending the summer studying instead of going to the World Cup and asked Yinsen about tutors.
• Yinsen told Illya she could choose whether to stay at Hogwarts, and she decided to make up her mind the following year.
• Scáthach chose to stay for one more year, Logan declined to return, and Rin Tohsaka and Leah decided to remain at Hogwarts until graduation.

Yinsen discussed the next school year and the Triwizard Tournament with Dumbledore before leaving the Wizarding World with his companions for the Moon Goddess. Logan returned to his adult form, only for Yinsen to secretly rig his cigars to turn him back into a child.

• Yinsen told Dumbledore that Logan would not return next year and that he himself planned to leave after the following year, while Dumbledore expected the Order of the Phoenix to confront Voldemort.
• Yinsen worried that Harry was unprepared for the Triwizard Tournament, and Dumbledore said Lupin had left to help Sirius while the Order investigated Voldemort’s Horcruxes.
• Dumbledore planned to hire a new Defense Against the Dark Arts professor, possibly leaving an opening for Death Eaters to infiltrate Hogwarts.
• Yinsen and the others packed their belongings, donated what they did not want, and left the Wizarding World for the Moon Goddess.
• Logan used a potion and changed clothes to return to his adult form, then teased Yinsen about remaining a child.
• Yinsen secretly tampered with Logan’s cigars so that smoking one would turn Logan into a child for a full day.

Yinsen enjoyed a more comfortable home life aboard the ship while dealing with Selene’s decision to avoid him until he looked older. After Little White fled at the prospect of being modified to eat magic stones, Yinsen considered bringing Fantastic Beasts to the island and checked on his teams in other worlds.

• Rin Tohsaka cooked Chinese food for Yinsen, who learned she could prepare most home-cooked dishes and looked forward to her and Shirou Emiya cooking aboard the ship.
• Selene dressed and left Yinsen after deciding not to be with him again while he looked like a child, leaving him frustrated and alone in his Wooden Cabin.
• Yinsen found Little White rolling in the snow and suggested modifying it so it could eat magic stones, but the bear shook its head and ran down the mountain.
• Yinsen considered using the Time-Turner to bring Fantastic Beasts and Pegasus to the island.
• Yinsen learned that O'Connell, Jonathan, and Maria Hill had returned from the G.I. Joe world with information and samples, while Soujun and Medea had joined Urameshi's team in the YuYu Hakusho world.
• Yinsen checked on Shirou Emiya and Illya, who had finished their first adventure and were packing to return after saying goodbye to their companions.

After a year of training in the Harry Potter World, Shirou Emiya demonstrated his improved combat skills in a sparring match with Yinsen. Yinsen praised his progress and asked whether he could project armor.

• Yinsen and the others gathered to assess Shirou Emiya after his year of training, but Yinsen ended up volunteering to test him.
• Shirou Emiya attacked with projected blades, Reinforcement Magecraft, and smoothly changing weapons, while Yinsen mostly parried with a Libra Golden Sword.
• After five minutes, Yinsen counterattacked and nearly struck Shirou Emiya with a spear thrust.
• Shirou Emiya joined his blades and unleashed Twin Flame Slash, which Yinsen caught and compressed without being harmed.
• Yinsen praised Shirou Emiya's progress and asked whether he could project the armor associated with the technique.

Yinsen helped Shirou Emiya and Rin Tohsaka decide how to balance their lives in the Type-Moon World with joining the Moon Goddess, while Illya reaffirmed that the ship was her home. After the group returned to the ship, Yinsen reviewed their other worlds’ affairs, and Maria Hill proposed a way to help Imhotep’s struggling religious sect.

• Shirou Emiya said he could project armor for less than a minute, and Yinsen advised him to consolidate his experience and build up his magical energy.
• Yinsen explained that the worlds’ time flows would be synchronized, and Rin Tohsaka chose to withdraw from school and remain on the Moon Goddess to study advanced magic.
• The group prepared to return to the ship after several days in the Type-Moon World; Shirou Emiya’s age was reduced, and Rin Tohsaka withdrew because she was moving abroad.
• Illya said she had nothing left to miss in her old world, and Cú Chulainn spoke with Yinsen about King Arthur and the possibility of meeting him.
• After a lavish meal at the Emiya Residence, Yinsen led the group back to the Moon Goddess and heard that Imhotep’s religious sect had stalled in its expansion.
• Maria Hill suggested that Imhotep promote a way to increase Warriors’ Combat Power, which could attract the Federation’s support.

Yinsen gave Imhotep a crystalline holy relic to channel believers’ faith into the Holy Light Cross, potentially growing its Small World into a heaven, then prepared to return to Hogwarts for the school year. He arrived with Scáthach, Rin Tohsaka, Leah, and Illya, where he told Dumbledore it would be his final year of study and asked him to look after the girls.

• Yinsen considered using believers’ faith to grow the Small World within the Holy Light Cross into a heaven where willing souls could enter after death.
• Yinsen gave Imhotep a crystalline orb that would direct believers’ faith into the Holy Light Cross and let them draw on Holy Light.
• Yinsen toured the Moon Goddess, tested its Teleportation Device, visited Diana, and prepared to return to the Harry Potter World as summer vacation ended.
• Yinsen gathered Scáthach, Rin Tohsaka, Leah, and Illya on the island and teleported with them to the Harry Potter World.
• Yinsen returned directly to Hogwarts and told Dumbledore that he would stop studying after the school year, asking him to look after the three girls.

Yinsen learned that the Triwizard Tournament’s age restriction could not stop him and publicly entered the competition despite being in Fourth Year. The chapter ended with him admitting that he no longer knew his own age, so the spell had no effect on him.

• Yinsen learned that Moody had been captured as part of the Order of the Phoenix’s plan, and Dumbledore carried a ring that would alert him if Moody’s life was in danger.
• At the opening feast, Dumbledore introduced the Triwizard Tournament, the visiting Beauxbatons and Durmstrang students, and Mad-Eye Moody, who was actually Barty Crouch Jr. in disguise.
• Slytherin students debated whether Yinsen was qualified to represent Hogwarts, and Yinsen told Draco Malfoy that the age limit could not keep him out if he wanted to enter.
• After students began submitting their names, Yinsen walked through the age-restriction barrier and dropped his parchment into the Triwizard Tournament while others were thrown back.
• Yinsen’s successful entry thrilled the Slytherins, and he explained that he did not know how old he was anymore, so the age-restriction spell did not affect him.

Yinsen and Harry Potter were named Hogwarts champions for the Triwizard Tournament, leaving the organizers to accept four contestants instead of three. As preparations began, Yinsen found himself newly popular at school, while Hermione told him that Harry wanted to speak with him.

• Dumbledore announced Viktor Krum and Pheobe Delacour as champions before revealing Yinsen Arendelle's name.
• Professor McGonagall objected that Yinsen was underage, but the Triwizard Tournament selected Harry Potter as a second Hogwarts champion and Barty Crouch insisted the contest continue.
• Yinsen told Pheobe that he had written his name on parchment and thrown it into the Triwizard Tournament, but she did not believe him.
• Dumbledore and the professors questioned Harry, who denied entering himself and said he did not know why he had been selected.
• The four champions began preparing for a tournament with three events spread across the school year, and Yinsen knew the first event involved facing a dragon.
• Hermione explained that Yinsen's popularity had risen since his selection and told him that Harry wanted to talk to him.

Harry told Yinsen that the first Triwizard Tournament task involved dragons, and Yinsen prepared to face his dragon without revealing his full strength. Before the task began, Yinsen punished Rita Skeeter for photographing Hermione and fabricating stories, then the contestants drew their opponents.

• Harry told Yinsen that the first task involved dragons, and Yinsen thanked him for the warning.
• Yinsen and Scáthach discussed Rita Skeeter's fabricated Daily Prophet article about him, and Yinsen decided to teach the reporter a lesson.
• The four contestants gathered in the waiting tent before the first task, and Hermione visited and hugged Harry and Yinsen.
• Rita Skeeter photographed the contestants and Hermione, but Yinsen crushed her camera, burned her quill, and cast Nightmares Galore on her before sending her and her assistant out of the tent.
• Dumbledore stopped Barty Crouch from pursuing the incident, and Barty began asking the contestants to draw their dragon opponents.

Yinsen faced the Swedish Short-Snout in the Triwizard Tournament’s first task and chose to confront it directly rather than sneak past it. As the dragon’s claw descended, it was suddenly covered in bloody cuts, leaving the crowd stunned.

• Pheobe Delacour calmly put her dragon to sleep and took its Golden Egg, while Viktor Krum damaged his egg during his attempt.
• Harry Potter used his Flying Broom to lead the Hungarian Horntail on an aerial chase and successfully claimed his Golden Egg.
• Yinsen walked straight toward the Swedish Short-Snout and redirected its blue flames into its face.
• The Short-Snout swung its claw at Yinsen, but the claw was suddenly sliced by countless unseen blades, and the injured dragon cried out in pain.

Yinsen defeated the Swedish Short-Snout and won the Triwizard Tournament’s first event, astonishing the spectators with his strength. Afterward, Hermione admitted she felt foolish for worrying about him, and Yinsen told her he was glad she considered him a friend.

• Yinsen restrained the Swedish Short-Snout with chains and vines, then knocked it unconscious with his Patronus Charm and took the Golden Egg.
• Dumbledore, Barty Crouch, and the spectators reacted with shock to Yinsen’s power, while Mad-Eye Moody worried about helping Harry win.
• The judges announced that Yinsen had won the first event, while Pheobe and Harry passed and Viktor came last after his Golden Egg was damaged.
• Hermione avoided Yinsen because she felt foolish for underestimating how strong he was, but Yinsen told her that her concern meant she saw him as a friend.
• Hermione affirmed that Yinsen was her friend, then asked whether he saw her as one too.

Hermione pressed Yinsen about his concealed identity, and he revealed that he was a powerful mage from another world who was pursuing godhood. She left with a new understanding of Yinsen and his friends, while Yinsen claimed he had already become a god in a sense.

• Hermione asked whether Yinsen came from an ordinary family and learned that Dumbledore and Snape knew his true identity.
• Yinsen brought Hermione to Snape's office so they could speak privately, and Snape treated Yinsen with respect.
• Yinsen described himself as a mage on the path to becoming a god and explained that he was not from Hermione's world.
• Hermione reconsidered the strange behavior and histories of Yinsen's friends, including Logan, Rin Tohsaka, and Scáthach.
• Yinsen told Hermione that, in a sense, he was already a god.

Yinsen prepared for the upcoming ball and discussed the Triwizard Tournament’s second task with Hermione and Dumbledore. He arranged protection for Hermione and left Dumbledore to choose a suitable hostage for him to rescue.

• Scáthach teased Yinsen about the girls around him, and he invited Illya to be his dance partner for the Hogwarts ball.
• Hermione asked whether Yinsen had solved the Golden Egg, and he gave her a protective necklace after learning she no longer wore her Time-Turner.
• Yinsen told Dumbledore that Illya and Scáthach should not be chosen as hostages for the underwater task.
• Dumbledore and Yinsen struggled to decide whom Yinsen should rescue, and Yinsen suggested Draco Malfoy before agreeing to let Dumbledore make the arrangements.