Yu-Gi-Oh! GX Terminology

Bio-Bands
bio bands were given to the students at duel academy by professor viper to montior their progess while dueling it is later discovered that they absorb the energy of the duelist while they are dueling and this energy is being used to resurect Yubel.

Electrodes
Electrodes are a kind of "collar" used in underground duels. They were first shown when Zane dueled against Mad Dog in an attempt to gain more power. When a duelist loses life points while wearing an electrode, a severe electric shock is sent through their body causing them great pain. After his duel with Mad Dog, Zane used them again in a duel against his younger brother Syrus. Frequent use of electrodes can caused someone to develop a severe heart condition, usually ending in death. The only known case of this is with Zane who presumably used the electrodes in several other duels not shown in the anime.

Duel Academy
Duel Academy is the setting of most of Yu-Gi-Oh! GX. It is a school that trains duelists to become professionals. It has three dorms: Slifer Red, Ra Yellow, and Obelisk Blue. It is owned by Seto Kaiba.

Genex tournament
The Genex Tournament, or GX tournament, was an event created by Chancellor Sheppard during Jaden's 2nd year at Duel Academy. It showed duelists such as Prince Ojin (a prince whom lost his country's Satellite Cannon to Sartorius after being subjected to the dreaded First Turn Kill), a reappearance by Blair (a young duelist appearing at Duel Academy with the hope of winning the tournament and getting into Slifer Red), Lucien Grimley (a duelist from North Academy who sold his soul to The Grim Reaper in exchange for drawing power), Frantz (an ex-card designer/duelist whom lost his job to Chumley and afterwards appeared at Duel Academy with a copy of The Winged Dragon of Ra, only to get beaten by Jaden thanks to Skyscraper 2 - Hero City, a card which Chumley had designed for him), and many others. Chazz was eventually declared the champion of the Genex tournament after defeating Blair Flannigan.

Light of Destruction
The Light of Destruction, known in Japan as The Light of Ruin, is an extraterrestrial being that possesses Sartorius when he had contact with the Ultimate D card. Highly infectous and dangerous, the Light of Destruction wreaks unholy havoc on the world in the second season. For billions of years, a white hole releases a mysterious energy called the Light of Destruction. When this energy reaches Earth, it causes several calamities such as dictatorships and wars. Ten years before the events of the second season, the Light of Destruction was released, infecting a card created by Aster's father, Destiny Hero - Plasma. When The D, known as Kyle Jables at the time, acquires the card by kidnapping (murdering in the Japanese version) Aster's father, it possesses him, causing him to develop an uncaring and sadistic personality. Afraid of what is happening to him, The D consults with a fortuneteller named Sartorius, who becomes possessed as well. After possessing Sartorius, it sets the stage for the events of the second season by amassing a cult of brainwashed students and acquiring a mind-control satellite that it will use to enslave the planet. It is ultimately sealed away, freeing Sartorius from its influence, due to the efforts of Jaden Yuki and Aster Phoenix.

Misgarth
The Misgarth Kingdom was the royal family of Prince Ojin. They were responsible for sending the brainwashing satellite, that Sartorius intended to use to make the world into members of the Society of Light, into space.

Scab Counter
A Scab Counter is a counter thst is given to a card that battles with Scab Scar-Knight. At the End Phase, the controller of that Scab Scar-Knight takes control of all monsters with Scab Counters.

Spirit Gates
The seven Spirit Gates are gates hidden deep below the Duel Academy, used to protect the Sacred Beasts. They can only be opened by obtaining the seven Spirit Keys, which can only be won in a duel. Nearing the end of the first year of Duel Academy, the gates are opened, and Kagemaru announces that the gates can be opened by posessing enough dueling spirit.

Spirit Partner
Spirit Partners are Duel Monster Spirits that have human partners. Their partners and any other humans that possess the ability are the only humans who can see and interact with them. It’s also possible to have more than one spirit partner. The following characters own or have the ability to sense a Duel Monster in one way or another:


 * Jaden’s main spirit partner is Winged Kuriboh. Later on, he’s also able to verbally communicate with the Neo-Spacians as well as Elemental Hero Neos.


 * Chazz’s main spirit partner is Ojama Yellow in the anime, and Light and Darkness Dragon in the manga. However, he is also able to see the other two Ojamas that make up the The Ojama Trio, The Dark Scorpions, as well as all the monsters in his 0-ATK deck.


 * Jesse’s main spirit partner is Crystal Beast Ruby Carbuncle. He’s also able to interact with the rest of the Crystal Beasts plus the ones floating around such as Tom’s Jerry Beans Man. He also considers all of his monsters his family.


 * In the GX manga, Kouyou Hibiki is the original owner of Winged Kuriboh before passing it down to Jaden. He too, is able to communicate with his duel spirit.


 * Chumley has Des Koala as his spirit partner.


 * Trapper doesn’t possess a spirit partner of his own, but nonetheless, wields the uncanny ability to not only see, but also trap duel spirit monsters.


 * Mr. Stein has the ability to only see his own monster, Scab Scar-Knight.


 * Though Sartorius can not see visually see nor speak to duel spirits, he is able to sense them due to his honed psychic abilities.