Slifer Red, known as Osiris Red (オシリス・レッド Oshirisu Reddo) in the Japanese and Castillian Spanish versions, is the lowest-ranked of the three dorms at Duel Academy. It has also sometimes being referred to as the "Red Dorm".
The students, save for a select few are categorized as being the weakest Duelists among the dorms, having very weak decks and poor strategies which cause them to lose most of the time. In some cases students from this dorm have never won a Duel at all and drop out.
Slifer Red has the worst dorm and the least to no privileges out of the three dorms. Upon seeing it for the first time, Syrus Truesdale referred to it as "an outhouse with a deck". Their welcoming feast was a small tray of rice, sardines and sauces held in a small dining hall. The only type of boat they have is a rowboat. Chazz Princeton has made the interior of the dorm more luxiorious for the students when he moved in. A prominent renovation is the single person living space Chazz added onto the building; it resembles a luxurious apartment (bath included), which includes a living room big enough to hold a party to Pro League duels. During the third year, Blaire Flannigan moves into it (to accommodate the fact she is the only girl in Slifer Red), as Chazz had temporarily moved back to Obelisk Blue.
The state of the dorm is likely designed as incentive for residents to either try advancing to a higher dorm and acquire a better standard of living or leaving the school.
The head of the Slifer Red Dorm, in the anime, was previously Professor Lyman Banner. After Banner (as Amnael, the 7th Shadow Rider) lost a Duel to Jaden Yuki his body was destroyed but his cat, Pharaoh, caught Banner's spirit in his mouth to stop him from leaving. In the manga the head of the Slifer Red Dorm is Midori Hibiki.
In the beginning of the anime Dr. Crowler expressed a great disdain for the students in this dorm, going as far as to set up stakeouts and sabotaging Duels to find any opportunity to expel Slifer students. The students in Obelisk Blue shared his dislike and usually exploited the Slifers' low ranks by calling them "drop-out boys" (In the dub this is replaced by terms such as "Slifer Slacker", "Slifer Slime", or "Slifer Scum"). However, as time continued, students from all dorms began flocking to Slifer Red. Examples include Alexis Rhodes, Tyranno Hassleberry, Syrus Truesdale and Bastion Misawa.
However, by the end of the series, the only student officially enrolled in Slifer Red appears to be Jaden Yuki and has graduated as a Slifer Red student and went on a journey.
The students wear a jacket that usually extends to the waist. The Jacket has a band which matches the color of the jacket at the cuffs of the arms. The jacket also has a white band around the shoulders that has a snap or button to keep the jacket closed and another band which also matches the color of the jacket wraps around the bottom of the jacket which also serves the purpose of keeping the jacket closed (although Jaden Yuki keeps his open). There is a white decorative shape with a darker red border on the chest of the jacket.
Some second-year (or higher) Slifer Red students (like Chumley Huffington) wear a different colored jacket, a version whose main color is white instead of red. Just like the previous jacket it usually extends to the waist. The jacket has a band which matches the color of the jacket at the cuffs of the arms. The jacket also has a red band around the shoulders that has a snap or button to keep the jacket closed, and another red band that wraps around the bottom of the jacket to keep the jacket closed. There is a decorative shape with a darker red border on the chest of the jacket.
Characters in Slifer Red
- Daitokuji-sensei/Lyman Banner (Former Dorm's Headmaster) (anime only)
- Midori Hibiki (Dorm's Headmaster) (manga only)
- Judai Yuki / Jaden Yuki (Graduated)
- Sho Marufuji / Syrus Truesdale (Promoted to Ra Yellow in his second year, then Obelisk Blue in second half of his third year.)
- Hayato Maeda / Chumley Huffington (Moved out of the school when he was hired by Industrial Illusions)
- Rei Saotome / Blair Flannigan (Snuck in during the first season but was officially accepted into Duel Academy in the third season, advanced to Obelisk Blue in fourth season)
- Jun Manjoume / Chazz Princeton (Stayed for second half of his first year, the first half his second year, and the first half of his third year, promoted to Obelisk Blue in second half of his third year)
- Kousuke Kunisaki / Gerard (Posed as a student)
- Chick (Posed as a student)
- Alice (Posed as student)