Shadow Realm

The Shadow Realm was alleged to be a place of eternal suffering where people could be sent to, explicitly designed by 4Kids for the Dubbed version of Yu-Gi-Oh! second series anime (with reference in Yu-Gi-Oh! GX to replace the concept of death).

The Shadow Realm as presented in the English-language version of the anime does not exist in either the original Japanese-language Yu-Gi-Oh! manga or anime series, although a "Dark World Series" (Yami no Sekkai) is mentioned in the manga and anime, but was never referred to as a place of eternal suffering that a human could be sent to.

Information
The Shadow Games were depicted as occurring in "another dimension", purported to be the Shadow Realm. It was this "dark dimension" (so named by Maximillion Pegasus) that was to form the basis for the English-language Shadow Realm, and as mentioned above, it was essentially created to serve as a substitute for death, or characters dying. The Loss of a Shadow Game, a fatal wound inflicted by a Duel Monster, the power of a Millennium Item, or any other mystical means will, rather than outright kill a character, condemn their soul to the Shadow Realm - "a softer defeat" in essence, as it is established that a soul could be extracted from the Shadow Realm if need be; Indeed, this was the entire basis for the Storyline of the Dubbed version of Duelist Kingdom, where Maximillion Pegasus was hoping to assemble all seven Millennium Items in the hope of restoring the body of his late wife, Cecelia, and rescuing her consciousness from the Shadow Realm. It is unclear if the souls or consciousness of a person is sent to the Shadow Realm if someone were to die from natural causes, as appears to be the case with Cecelia.

The very concept of the Shadow Realm is often derided, mostly for the basic fact that it is a result of the censorship of some of the darker aspects of the show, but it is also partly because some of the more preposterous insertions of the Shadow Realm.

For example, when facing the conjourer Arkana, Yugi Muto comes under threat from a "Dark Energy Disc" which, if it touched him, would send him to the Shadow Realm. In the Japanese version, the disks were simply buzzsaw blades that would dismember the loser's feet, probably resulting in death.

Similarly, the Shadow Realm was used during a tag-team duel that involved Yugi Muto and Seto Kaiba dueling Lumis and Umbra atop a skyscraper in Domino City, famous for its hollow interior. In the English-language version, the windows they stood on has a small explosive device on them, which would cause a small explosion, resulting in the glass shattering when each Duelist lost, dropping them into a "portal", which would then transport the unfortunate victim to the the Shadow Realm. In the Japanese-language version, the windows shatter as they do in the Dub, but here, the duelist would simply fall to their death, falling all the way to the floor. This can be further evidenced by Umbra being prepared with a parachute, which he deployed when his window shattered, after he lost all of his Life Points, leaving his team-mate Lumis to surrender the Duel, and eventually has his mind taken over by Marik and his Millennium Rod.

Conversely, on occasion, the idea intersects with some of the original visuals - for instance, when Marik Ishtar does away with Mai Valentine's soul, visuals distinctly show her soul to have been relocated to another plane, which the English-language version is then able to refer to as the Shadow Realm.

Tying the concept together towards the show's conclusion, the demon, Zorc Necrophades, is credited with the creation of the Shadow Realm in the English-language version. Some characters are pulled out of the Shadow Realm in the English anime and the English-language video games.

The Shadow Realm is similar to (and probably based on) the religious concept of Hell.

Known residents

 * Ghost Kaiba: Originally Seto Kaiba's evil side, he was banished to the Shadow Realm when Yami Yugi used a Mind Crush on Kaiba, targeting the evil rather than Kaiba himself. Maximillion Pegasus later helped him escape, but after Yami Yugi beat him in a duel, he banished him back to the Shadow Realm with a Mind Crush.
 * Panik: After Yami Yugi beat Panik in a duel, Panik attempted to kill him, but the Millennium Puzzle shielded him and he banished Panik to the Shadow Realm with a Mind Crush.
 * The Mugger: While threatening Téa, the mugger was challenged to a card draw game by Yami (who had taken over the unconcsious Yugi), who won and used a Mind Crush to banish the mugger's soul to the Shadow Realm.
 * Seeker the Rare Hunter: After losing to Yami Yugi in a duel, Marik used the Millennium Rod to take control of the Rare Hunter's body and trap his mind in the Shadow Realm.
 * Lumis: Once it was clear there was no way Lumis could win, Marik took over his body and trapped his soul in the Shadow Realm, as after Marik left him and he collapsed, Kaiba walked over to his lifeless form and picked up locator cards.
 * Bonz: After being defeated by Yami Bakura in a duel, Bakura trapped him in the Shadow Realm, along with Sid and Zygor. Presumably he never chose to release them.
 * Sid: After Yami Bakura defeated Bonz, he trapped Sid in the Shadow Realm along with him and Zygor. It is unknown if he ever released them.
 * Zygor: After Yami Bakura defeated Bonz, he trapped Zygor in the Shadow Realm along with him and Sid. If is unknown if he ever released them.
 * Mr. Ishtar: Who was sent to the Shadow Realm by Yami Marik with the Millenium Rod.
 * Mai Valentine: After Yami Marik defeated her in a duel, he used his Millennium Rod to trap her soul in the Shadow Realm, which looked slightly similar to a Mind Crush in that the negative effect was used (but not the glass effect). She was later released when Yami Marik was destroyed.
 * Bakura: After Yami Bakura was beaten by Yami Marik, he vanished into the Shadow Realm, along with the original Marik's soul. However, Marik was still able to control Téa, and Yami Bakura hid inside Yugi's Millennium Puzzle (as he had placed a bit of his soul there in an earlier episode), thus the only one who was truly banished to the Shadow Realm was the original Bakura. He was later released when Yami Marik was destroyed.
 * Mushara: While wanding through the tomb with Ahmet and Grandpa, he was slashed by a statue and fell into a pit of shadows, leading to the Shadow Realm.
 * Weevil Underwood: Temporarily sent to the Shadow Realm by Yami Bakura while along with Rex attempting to steal Yugi's Millennium Items (mistaking them for god cards).
 * Rex Raptor: Temporarily sent to the Shadow Realm by Yami Bakura while along with Weevil attempting to steal Yugi's Millennium Items (mistaking them for god cards).
 * Mokuba Kaiba: Temporarily sent to the Shadow Realm by Yami Bakura to make Kaiba duel him.
 * Karim: Gave all his diadankh energy to Shada so the Twin-Headed Jackal could destroy Giant Axe Mummy, and since his diadankh was depleted, his soul was trapped in the Shadow Realm. Was later released when Yami Bakura and Zorc were destroyed.
 * Aknadin/Shadow Magus: Destroyed by the Blue Eyes White Dragon, trapping his soul in the Shadow Realm. Was later released when Yami Bakura and Zorc were destroyed.
 * Hasan: His diadankh energy was depleted when he jumped in front of the guards to protect them from Zorc's attack, causing his soul to go to the Shadow Realm. Was later released when Yami Bakura and Zorc were destroyed.
 * Shada: His diadankh energy was depleted when he jumped in front of the Pharaoh to protect him from Zorc's attack, causing his soul to go to the Shadow Realm. Was later released when Yami Bakura and Zorc were destroyed.
 * Isis: Zorc destroyed her Winged Dragon Guardian of the Fortress, depleting her diadankh energy and trapping her soul in the Shadow Realm as she fell. Was later released when Yami Bakura and Zorc were destroyed.
 * Shimon: His diadankh energy was depleted when his Exodia was destroyed by Zorc, causing his soul to go to the Shadow Realm. Was later released when Yami Bakura and Zorc were destroyed.
 * Seto: His diadankh energy was depleted when his Blue Eyes White Dragon was destroyed by Zorc, causing his soul to go to the Shadow Realm. Was later released when Yami Bakura and Zorc were destroyed.

Possible residents

 * Solomon Muto: Pegasus trapped his soul inside a card, and could have possibly been the Shadow Realm, or similar to it. Pegasus later released him after his defeat by Yugi.
 * Mokuba Kaiba: Pegasus trapped his soul inside a card, and could have possibly been the Shadow Realm. Pegasus later released him after his defeat by Yugi.
 * Seto Kaiba: Pegasus trapped his soul inside a card, and could have possibly been the Shadow Realm. Pegasus later released him after his defeat by Yugi.
 * Umbra: In the duel against Yugi and Kaiba, Kaiba summoned Obelisk the Tormentor and took out all of Umbra's life points, causing the "shadow barrier" glass to break and causing him to fall into the Shadow Realm. Though he activated a parachute, his mind appears to have been trapped to the Shadow Realm, as he was quite motionless. However, it is debatable that he may have "stopped the effect" in time when the parachute caught on a pole. Whether or not he was truly sent to the Shadow Realm remains unknown.

Duels that took place in the Shadow Realm

 * Yugi vs Pegasus (in the duel in which Pegasus stole Grandpa's soul)
 * Yami vs Yami Bakura (in the duel where Yugi, Joey, Téa, Tristan, and Bakura are all cards)
 * Yugi vs Pegasus (the finals of Duelist Kingdom)
 * Yami Bakura vs Bonz (in Battle City)
 * Mai vs Yami Marik (in Battle City)
 * Yami Bakura vs Yami Marik (during Battle City)
 * Joey vs Yami Marik (in Battle City)
 * Yami vs Yami Marik (Battle City finals)
 * Seto Kaiba vs Yami Bakura