ALL spoilers will be unmarked ahead. Beware major spoilers.
Shadi (シャーディー; Shaadii)
A mysterious man from Egypt, Shadi was the guardian of ancient Egyptian tombs and the modern day holder of the Millennium Ankh/Key and Scales. He uses the Ankh to enter a person's soul room and redecorate their rooms to control the individual to his liking, and uses the Scales to measure a person's sins via a Weighing of the Soul Shadow Game and punish them as he sees fit. He first makes his appearance in the manga after Yugi's Millennium Puzzle is taken away by Kanekura and acts as the Big Bad of the Trial of the Mind arc where he poses a series of Shadow Games onto Yugi as a test.
Afterwards he comes and goes as he pleases, with a slightly heavier presence in the anime. His role is crucial to some of the villains' backstories, including Pegasus and Marik. Throughout the series, he is an emotionless person who only seems to be interested in gathering the Millennium Items.
For information on Hasan, his non-player character in the Shadow RPG, see Yu-Gi-Oh! Ancient Egypt.
- Adaptational Heroism:
- In the second anime, he's a little more noble than his other portrayals. He doesn't brainwash people like in the other versions, manages to save Honda and Otogi's lives at one point during Battle City, and in the final arc he gets the role Bobasa originally served in the manga, Heroic Sacrifice included (though Bobasa reveals himself to, in fact, be Shadi in disguise in the manga).
- In the English dub of The Dark Side of Dimensions, while teaching his adopted children about the Quantum Cube, he does not twist his teachings, and tells Bakura's father to try to wear the Millennium Ring with regret. In the original Japanese, he allows him to try to wear it but with no hint of regret.
- Asshole Victim: He was killed by Dark Bakura in the flashbacks in The Dark Side of Dimensions.
- Big Bad: Of the first real arc of the manga. He is not actually evil, but he abides by the Egyptian standards of morality.
- The Cameo: He gets one in Yu-Gi-Oh! Reshef of Destruction, explaining the backstory to the game.
- Chekhov's Gunman: In the second anime series, where he doesn't make an appearance until the end of Duelist Kingdom. Until then, he's just a figure from one of Pegasus' paintings. In the manga, the cast recognizes him from the painting as they have met him before.
- The Chessmaster: Hasan in the Pharaoh's Memory World being revealed as Shadi might have been because of Shadi himself interfering with the Shadow RPG to save the Pharaoh. He also seemed to work behind the scenes to get the Pharaoh to the afterlife and seal the Millennium Items. See The Unfettered below.
- Composite Character: An odd variation in the Millennium World story, as in the anime version he also serves Bobasa's role, though Bobasa himself still appears, albeit with a drastically different personality than his manga counterpart. In the manga, Bobasa is Shadi in disguise.
- The anime version also implies that he is the spirit of Priest Shada combined with that of Priest Karim, as Karim had died through giving his life force to Shada. This explains why Shadi holds both the Ankh and Scales.
- Dead All Along: This is the only consistent thing about him across the series. The Dungeon Dice Monsters game has him as a disciple of Anubis, which may explain some of it.
- In the second-series anime, he's possibly the combined reincarnation of Shada and Karim who was killed by Yami Bakura five years ago.
- In the dub, he's a millennia-old spirit whose body was destroyed by Thief King Bakura.
- The manga has him be Hasan, a spirit who pledged loyalty to the Pharaoh from the afterlife and returned in Shadi's form to protect him, and was killed by Yami Bakura five years ago.
- Yu-Gi-Oh! The Dark Side of Dimensions has him as a man with supernatural powers who was killed by Yami Bakura as soon as four-year-old Ryou put on the Ring.
- Dull Eyes of Unhappiness: His eyes always look like this due to him being dead.
- Early-Bird Cameo: In the second anime series, his portrait is briefly shown for the first time in episode 8 of the anime, and once again in episode 28. He makes his debut in episode 40. In the manga, since Shadi's arc happened before Duelist Kingdom, it's a Call-Back.
- Evil Cannot Comprehend Good: Seeing the power of friendship in action practically blows his mind.
- Friend to All Children: How he's portrayed in Yu-Gi-Oh! The Dark Side of Dimensions, adopting a group of orphans who have all suffered and granting them the power of the Plana.
- Heroic Sacrifice: Played the special NPC Hasan during the Shadow RPG, and ended up shielding the main cast, Atem and his priests from Zorc's Inferno.
- Journey to the Center of the Mind: He did this a few times with his Millennium Ankh, entering the "Soul Room" of the person of his choice. He's also capable of remodeling said rooms, thus altering that person's personality, up to making them into his puppet.
- Mind Rape: His Millennium Key lets him brainwash people, and the Scales allow Ammit to enter their soul, eating them if they fail his tests.
- Mind Screw: Shadi has the reputation for being the most confusing character in the entire franchise thanks to his enigmatic nature and for having four identities associated with him (Teen Shadi, Adult Shadi, Hassan and Bobasa). The conflicting, bare-bones backstories between adaptations don't help.
- Named by the Adaptation: The Dark Side of Dimensions names him Shadi Shin, though the manga and both anime just call him Shadi.
- Not So Above It All: He's extremely serious most of the time, but in his first appearance he playfully ruffles Yugi's hair.
- Older Alter Ego: When Yugi meets him, he appears as an adult man. When Pegasus meets him in Egypt in the manga, he appears as a young boy.
- Retcon: The Dark Side of Dimensions changes his appearance slightly, has him raise Aigami, Sera, Mani, and the planners, and gives him powers he's never shown to have before, such as wielding the Quantum Cube, which can directly erase people from existence and send them to other dimensions. He can also transfer his powers to others, but they will lose them if the Pharaoh is reborn into the world a second time.
- Riddle Me This: All of his Shadow Games are riddles and puzzles. His very existence is a riddle.
- Shadow Archetype: To Yami Yugi. Shadi has the same take-no-prisoners approach to people who wronged him that Yami Yugi originally had. Their encounter paved the way for a slightly more forgiving protagonist who would give his opponents chances to redeem themselves (though he didn't outgrow the Penalty Games until halfway through Duelist Kingdom).
- Sink-or-Swim Mentor: He tests Yugi by endangering his friends and nearly killing them.
- Stealth Hi/Bye: He can appear and disappear seemingly at will, more so in the anime.
- The Unfettered: He commits himself to his mission of assembling the Millennium Items. He kills Kanekura and the man who intended to buy the Millennium Puzzle, temporarily brainwashes Yoshimori and Anzu in order to get Dark Yugi out from the Millennium Puzzle and somewhat manipulates Pegasus.
Shizuka Kawai (川井 静香; Kawai Shizuka) (Serenity Wheeler)
Jounouchi's sister who lost her eyesight, Jounouchi entered Duelist Kingdom to win the money to pay for her operation to heal her. She accompanies the gang for the later parts of Battle City.
She never plays any games in the manga; her role in Battle City is to give Jonouchi her support. In the anime, they play her up and let her duel in the Virtual World arc. The one time she duels, her deck doesn't have a theme other than the monsters are all female and/or religious. Her trump card is St. Joan.
- Action Girl: In the anime; manages to play the part by the end of her duel with Soichiro Ota.
- Adaptational Badass: She mostly exists in the manga to be Jounouchi's motivation and support. Although she has the same role in the anime, she's more proactive—she saves Jounouchi from drowning instead of Kaiba and she actually gets to duel (and win) in the Virtual World filler arc.
- Adaptation Dye-Job: Her hair is blonde in a piece of manga artwork, but she's lavender-haired in the Toei anime and a redhead in the second anime.
- Adorkable: She's shy, cute, and plays games if her appearances in Dungeon Dice Monsters and Nightmare Troubador are any indication, she definitely checks out.
- Amazon Brigade: Her deck is all female monsters, though they range from the exceptionally girly Forgiving Maiden to Fallen Angel Marie the Fallen One to Lady of War St. Joan.
- Ascended Extra: She's mostly a minor character in the manga and only shows up prominently in the Battle City arc. She has more screentime in the anime, due to the addition of the Virtual World filler in Battle City.
- Badass Adorable: In the anime. Sweet, cheerful, and also the one to ultimately take down an opponent in a three-on-one duel.
- Beauty, Brains and Brawn: The Beauty to Anzu's Brains and Mai's Brawn. One could argue that in her duel alongside Ryuji and Honda she also plays this role, with Honda as the muscle, and Ryuji the brains.
- Beginner's Luck: Against Soichiro Ota. Sure she has lots of help from Honda and Ryuji, but the fact remains that she managed to take him down with cards she herself had picked out, despite not having a clue what most of them did.
- Big Brother Worship: Like Mokuba, she loves her big brother, despite being separated from him for years. In the anime, her love for Jonouchi extended to her jumping in the river after having her eye surgery. Talk about devotion.
- Big Damn Heroes: Before she removed her bandages, the anime plays her off as an Ill Girl who needs escorting and to be with someone. What does she do right as she takes them off? Dives into an ocean from a pier, and saves her drowning brother.
- Blonde, Brunette, Redhead: The Redhead, in the anime.
- Chekhov's Gun: At the start of the duel with Soichiro Ota, we see her specifically selecting St. Joan. Guess which card takes out Ota's Perfect Machine King?
- Dude Magnet: In the anime both Otogi and Honda fight for her affections.
- Grew a Spine: She wasn't a coward at first, but she spends most of her duel with Soichiro scared and confused. Towards the end, she finally develops a backbone and comes back strong, taking Soichiro down after Ryuji fails.
- Heroic BSoD: After Honda is defeated by Soichiro Ota.
- Ill Girl: During the Duelist Kingdom arc, where she's going blind and Jounouchi wants to win the prize money for her operation. The Toei anime gave her a generic illness.
- The Ingenue: She's sweet and idealistic, even while she's losing her eyesight and requires expensive surgery to save it.
- Best shown after Yugi's defeat of Marik in the anime (the following is a scene directly from the manga that originally had Ryo Bakura instead of Shizuka), and Mai should be back. She appears to be the same, and Jonouchi's really worried, even saying he'd do anything to get her back... only for Mai to start laughing, saying he fell for it hard, and thanking Shizuka for helping her. An utterly-confused Jonouchi looks at her, and she simply sticks her tongue out as she giggles.
- Jeanne d'Archétype: Her trump card, St. Joan, who is obviously modeled on Joan herself, and with which she takes down Big 5 member Nezbitt.
- Lady of War: Not Shizuka herself (though she certainly tries) but her trump card, St. Joan who with 2800/2000 is one of the better female cards in the game, and at the time the show was made, was one of the strongest Fairy monsters around. She's specifically modeled on Joan of Arc and has the looks to prove it.
- And then, in the one time she duels with some bits of help, she takes down one of the Big 5.
- Let's Get Dangerous!: In the anime; the duel between Yugi and Jounouchi during Battle City (rather, its consequences), in which she fearlessly jumps into the sea to rescue Jonouchi after he sacrifices himself for Yugi.
- Light Feminine and Dark Feminine: The light to Mai's dark (one of two).
- The Load: In anime filler, she starts out as this in her duel with Soichiro Ota, repeatedly requiring Honda and Otogi to bail her out (in her defence it was her first ever duel and she had to pick out her cards herself). She manages to take a level in badass and transition to Action Girl before the end of it.
- Meaningful Name:
- Shizuka means quiet, or silence. Her English name, Serenity, reflects this.
- Her Japanese surname, Kawai (川井) sounds like "kawaii" (かわいい), the Japanese word for "cute", and she is the cute little sister archetype.
- Nice Girl: One of, if not the kindest characters in the show.
- Oblivious to Love: She didn't realize that Anime Honda liked her and she called him her friend.
- Plucky Girl: She has her ups and downs, but still tries to do what she can.
- Shipper on Deck: In the Toei anime she tried to set her brother up with her nurse, Miyuki. In the second anime, she seems all for a potential Jonouchi/Mai pairing.
- Took a Level in Badass: In terms of the anime. You can spot the exact moment in the duel with Ota/Nezbitt where she decides to say "screw you" and starts channeling her brother for all she's worth.
- Vague Age: A photo of her in Joey's wallet shows her in middle school, but nothing is ever specified. Commonly, her age is thought to be around 13 years old.
Cyndia (シンディア; Shindia) (Cecelia Pegasus)
Pegasus' lover/fiancée (wife in the dub). Her death led to the creation of the card game and the Duelist Kingdom arc.
- Bit Character: She is one, although she is important to the plot. She also serves as a Foil to flesh out Pegasus' character through his backstory.
- The Cameo: In Yu-Gi-Oh! Reshef of Destruction, her portrait can be seen in a room in Pegasus' Castle. In Yu-Gi-Oh! R, Pegasus shows the card he made for her to Tenma Yakou in a flashback.
- Chekhov's Gunman: Her portrait is next to Shadi's in Duelist Kingdom. At first it isn't that significant, then Yugi's friends notice it in Pegasus's dining hall. Her significance to the story was revealed at the end of Duelist Kingdom.
- Childhood Friend Romance: With Pegasus. They were around 10 years old when they met. Unfortunately, it didn't last for too long.
- Early-Bird Cameo: In episode 8 of the anime and chapter 73 of the manga, her portrait can be seen next to Shadi's for a brief moment. She is properly introduced when Croquet tells Pegasus's story to Yugi in the manga, or when Anzu finds his journal and reads it out loud in the anime.
- Ill Girl: She died suddenly and unexpectedly of an unnamed illness.
- Kiss Me, I'm Virtual:
- She would have been brought back in Solid Vision form if Pegasus' plan hadn't failed.
- Also during Pegasus' vision after he receives his Millennium Eye - she's just an illusion.
- The Lost Lenore: Her tragic death informs Pegasus' entire character arc. Had she lived, not only would he be an almost completely different man, but the events of the entire series would have to shift dramatically.
- The Muse: In the dub, she inspired Pegasus to paint. Somewhat more ambiguous in the original, but it's still obvious that Pegasus loved painting pictures of her.
- O.C. Stand-in: While she's a canon character, nothing of her personality is known.
- Ojou: Implied; she met Pegasus when they were children at a party his wealthy father held, which indicates she was most likely at the same social status as him.
- Only One Name: Her surname is never given in the manga or the anime. This is averted in the dub, where she has Pegasus's surname from being his wife.
- Plot-Based Photograph Obfuscation: In the manga, when the portraits of her and Shadi are shown for the very first time when Pegasus is reading his Funny Rabbit manga, the top half of her face can't be seen. Dialogue and other objects conveniently obscure the entire portrait on a few occasions, while Shadi's is perfectly visible.
- Posthumous Character: She only appears in flashbacks.
- Satellite Character: Nothing's known about her outside of her relationship with Pegasus.
- Small Role, Big Impact: Her death was not only the motivating factor of the entire Duelist Kingdom arc, but also resulted in Duel Monsters' creation, indirectly contributing to the remaining arcs of the series and bringing about every single spinoff series.
- Something About a Rose: She is represented by roses, and Pegasus remembers her death as her being swallowed up in a rose that burst into petals.
- Spell My Name with an "S": Her original name is シンディア, which can be transliterated as Cyndia, although some spell it as Cynthia or Cindia. Then there's her dub name, Cecelia Pegasus, which becomes Cecilia, despite the fact that the proper dub name was shown in episode 40.
- Star-Crossed Lovers: With Pegasus.
- Together in Death: With Pegasus in the manga, according to Kazuki Takahashi.
- Voiced by: Anzaki Motomu (JP), David Wills (EN)
The previous head of the Ishtar clan was Marik and Ishizu's father, as well as Rishid's adopted father. Mr. Ishtar is a very strict tomb keeper who believes that guarding the Pharaoh's tomb is more important than his family. He treats Rishid like a slave while abusing him, and forces Marik to undergo the tomb keeper ritual, creating Dark Marik. When Mr. Ishtar tried to kill Rishid for letting Marik and Ishizu head into the outside world, Dark Marik awakened and skinned off Mr. Ishtar's back (in the English dub, banished his soul to the Shadow Realm), killing him.
- Abusive Parent: Between refusing to let Marik go outside, neglecting Ishizu and treating Rishid like a slave, Mr. Ishtar is not exactly a parent role model.
- Asshole Victim: Admit it: You're actually cheering when Dark Marik goes to town on this guy.
- Cruel and Unusual Death: Skinned alive by Dark Marik in the manga, stabbed to death in the anime, sent to the Shadow Realm (where your soul would be shredded) in the dub. None of his fates were quick and easy.
- Entitled Bastard: He thinks just because he let his wife bring him inside instead of letting him die as a baby that he has every right to make Rishid his slave and kill him, thinking he owes him his life.
- Hate Sink: A horribly abusive parent, he is not likable in the slightest.
- Knife Nut: More notable in the manga, where he not only uses a searing-hot knife to carve the tomb inscriptions into Marik's back but also uses said knives to punish Rishid for letting Marik go outside (the anime toned this down to him "merely" whipping Rishid).
- Knight Templar: He was unable to get what he was doing wrong, thinking he was in the right even when he faced death.
- Lack of Empathy: All he cared about AT ALL was his duties, the only reason he was protective of his son was because he needed a male heir. Everyone else he either neglected or treated like a slave.
- Posthumous Character: Killed by Dark Marik five years before Battle City.
- The Sociopath: He didn't care about people at all unless they are of use. He only cared about Marik because he needed a male heir and he didn't care that his wife was dying as long as he had a son.
- Unwitting Instigator of Doom: He had no intention of screwing with Marik, but his actions resulted in Marik's actions during Battle City.
- Well-Intentioned Extremist: All he wanted to do was to protect the Pharaoh's tomb, but he took his job way too seriously.
- Whip It Good: In the anime he whips Rishid as punishment for letting Marik go out.
- Voiced by: Akari Hibino (JP)
Marik and Ishizu's mother, as well as Rishid's adopted mother, who found him abandoned. She later dies giving birth to Marik.
Bobasa (ボバサ; Bobasa)
- Voiced by: Yuu Mizushima (JP), Sean Schemmel (EN)
In the manga, he's a tombkeeper and a servant of Shadi's who helps guide the Yugi and the others into the Pharaoh's Memory World as non-player characters in the Shadow RPG. In the anime, he's an NPC who joins Yugi and friends after they follow Yami Yugi/the Pharaoh into his memories and helps them discover where the temple that holds his name is located.
For information on his true form (in the manga), Hasan, see Yu-Gi-Oh! Ancient Egypt.
- Adaptation Personality Change: In the manga he's a fairly serious and intelligent character. In the anime he's mainly a source of comic relief and is fairly simple minded.
- Big Eater: When the gang first find him, he's busy eating two huge piles of fruit, and keeps eating when Anzu tries to question him.
- Big Fun: Again, in the anime. He's primarily a comical character and also incredibly friendly.
- Decomposite Character: The anime made him a completely separate character from Hasan and Shadi.
- Mythology Gag: In the anime, he and Hasan are voiced by the same actor. This is because in the original manga they were infact the same character (specifically Bobasa's "master" Shadi), although in the anime only Shadi turns out to be Hasan's alter-ego. Possibly also serves as a case of Not His Sled.
- Nice Guy: Cheerful and friendly.
Arthur Hopkins (アーサー・ホプキンス, Aasaa Hopukinsu) (Arthur Hawkins)
Arthur Hopkins was an unnamed character in the original manga, who was Sugoroku Mutou's American gaming buddy who gave him the rare Blue-Eyes White Dragon card. He is only seen in a photograph. He is given an ascended role in the anime, where he is an archaeologist interested in Duel Monsters and its connections to Egypt and Atlantis. His granddaughter is Rebecca.
- Ascended Extra: In the original manga, he was just a background character only seen in a photo. He's given a bigger role in the anime with his anime-created granddaughter Rebecca.
- Adapted Out: She is not mentioned in either anime.
- Ascended Extra: Despite being dead, only mentioned once in the manga, and not mentioned at all in either anime, she's a popular character in fan fiction, both as herself and to deepen Ryo's character.
- O.C. Stand-in: While she's a canon character, nothing of her personality is known.
- Posthumous Character: She and Mrs. Bakura died before Bakura moved to Domino.
- Retcon: Her death seems to be this, as in Ryo's letter he asks her how school is, and later says his family is alive but away. A supplementary book later confirmed Amane and her mother were dead and he wrote letters to them in heaven to cope.
- Too Good for This Sinful Earth: Implied with her young age and her name, which has the meaning of "heavenly sound."