Ikki Tousen - Terminology

Terminology

Magatama (勾玉?, lit. "Sacred bead")
Magatama are jewels worn as earrings by all fighters which contain the spirits and essence of warriors from the era of the Three Kingdoms in ancient China. How they found their way to Japan is a mystery. Magatama impart their power and fate upon each fighter (regardless of age or gender; all of the characters from this period are male, but most of the cast are young girls), which range from average to incredibly powerful, but come with the will of the spirit within and ultimately their fate, which usually tends to be tragic and painful. However, a few characters seem to be able to overcome their fate, even though the cycle has played over repeatedly for 1800 years. Not every fate is the same however; numerous important characters are missing, and some relationships and obviously personalities have been drastically altered, but the end results are significantly analogous. Some magatama are very selective; others can switch their magatama, increasing their own personal power. They also indicate a fighter's skill and power by a distinctive color related to the Olympic medal system, which often tends to be misleading with certain characters. The ambiguity of this is further enhanced by the anime's introduction of Hakufu's jade magatama (which was briefly replaced with a red when she was possessed by Totaku).
Gyokuji (玉璽?)
The Imperial Seal supposedly found by Bundai Sonken, Hakufu's father. It is a large jade seal that serves a role similar to a Royal Crown. Whoever carries it is granted authority over all the other nations, but it expectedly becomes a big target for everyone. Seito Academy originally held it before Toutaku stole it, but it eventually went to Ryomou from Ryofu, who passed it to Saji before it finally returns to Seito.
Dragons of Haou
The Ruling Dragon, or Shōryū (literally Dragon Lord), is an enigmatic entity or entities resembling a massive oriental dragon conferred uniquely upon the three destined rulers of the Three Kingdoms period: Hakufu, Sousou and Ryubi. It is proof of their birthright as conquerors. They confer massive power onto each of them, putting them well above A-rank regardless of their own skill, though each manifestation varies. Ouin managed to stop Hakufu's first manifestation fairly easily but his arm was broken in the attempt, however Koukin was only able to subdue it the second time with both a Hyakuhekitō and Ukitsu's help.
They do, however, create terrible destructive impulses that differ for each character. Hakufu's manifests a berserk, sadistic, psycho-sexual monster, but less so than Ryubi and Sousou. Sousou's dragon is psychotic and the most malicious but otherwise completely in control, while Ryubi's is completely out of control to the point of suicide and self-mutilation. It is also the most evil, radiating deathly energy that consumes the life around it.
In addition to the three Ruling Dragons, other characters in the series have been shown to harbor dragons as well. Because of the qualities of Ryubi's dragon, Kaku believed Totaku may have possessed a dragon of his own. As a result of Ryubi's dragon first awakening three years ago and the ensuing battle its presence caused, Ryomou possesses a dragon as well. However, only Saji, Teifu, and the main characters of Seito (excluding Ryubi) are aware of this fact. Koumei is believed to harbor a dragon as well, as Ryubi witnessed it for a brief instant.
It has also been hinted several times in both the anime and manga that Cho-un also harbors a dragon, as whenever she opens her eyes, her pupils are cat-like and yellow in color, very similar to those of the awakened fighters. Likewise in the manga, Kanu displayed identical pupils after Gakushin's aborted attempt to invade her mind, during her fight with Kyosho's Three-Pillared Gods.
Typically when a dragon manifests, the eyes of the fighter either glow red or turn yellow with cat-like slits. The forearms manifest bulging veins, which can sometimes extend over the entire body, and fangs are also sometimes shown. In the second season of the anime, each dragon is of a different color; Hakufu's is blue, Sousou's is red, and Ryubi's is gold. Unlike the manga, Ryomou's dragon appears to be her own and not Ryubi's, and is black. Koumei is also shown with a silver dragon, referred to as the Crouching Dragon.
Hyakuhekitō
A set of 5 legendary Chinese jian made of jewels. Supposedly made by Cao Cao in ancient China, they are each named after an animal: Dragon, Tiger, Sparrow, Bear, and Horse. Incredibly evil and powerful swords capable of beating even the Dragons of Hao. Originally all five were embedded in a large boulder on Chosho's property and sealed with chi, making them impossible to remove. Toutaku extracted an unnamed sword while studying and failing under Chosho. Kanu also trained under Chosho and extracted one of the blades, but broke a sword named Kusanagi in half, leaving the remaining half of the blade still embedded in the rock. It is unknown which of the five it is. Teni had Dragon likely passed to her from Chiba, and Hakufu managed to remove Tiger completely intact, but Saji recovered it and entrusted it to Koukin so he could stop Hakufu's dragon. Toutaku later destroyed the boulder, freeing the remaining two and the other half of Kusanagi which he brought with him to his grave. Sousou recovered all of them and two of the intact blades were seen under high security at Kyosho.
Saji had a sword made of jade, and it is also an ancient sword. It is unknown if it is one of the five, as it is named Dragon, but Teni had Dragon distinctly named as a Hyakuhekitō, so it is likely another ancient sword. On a sidenote, a katana named Muramasa lies in Gogun Academy. All of these are so far absent from the anime.
Seiryutō (青龍偃月刀, lit. "Holy Dragon Blade"?)
Guan Yu's legendary Green Dragon Crescent Blade, accurately depicted and carried by Kanu at all times. Supposedly made of jewel rather than metal, this may in fact be allegory, as a particularly high-quality type of steel in Japan is known as tamahagane, or "jewel steel". Extremely powerful and possessing massive chi, it was melted during a battle against Ryuubi's dragon 3 years prior to the start of the series, but was apparently repaired at some point.
Dragon Jade
A new artifact introduced in Ikki Tousen: Dragon Destiny. It is a gold oriental dragon coiling around a gold orb sealed in a glass orb. It is said that the Dragon Jade has the ability to tame a dragon (though has failed to do so as of yet) as well as change the destiny of any fighter, something otherwise impossible. It is extremely mythical, and up until Ryomou found it, everyone thought it didn't exist; in fact, very few even knew about it in the first place. A mysterious monk (who is presumed to be the same one who was with Kaku earlier on) told Ryomou about who proceeded to find it. Ryomou, however, was ambushed and badly injured by Teni, who was finally defeated by Shiryu who stole it and brought it to Kanu. According to the monk, it will only activate when all three dragons are roused and brought together, but Ryomou is seen holding it and activating it, creating a blue aura, making her left eye glow blue, then summoning a black dragon.
Towards the end of Dragon Destiny, the Dragon Jade truly activates due to the presence of all the three dragons (Sousou's Red Dragon, Ryubi's Yellow Dragon, and Sonsaku's Blue Dragon) in its vicinity and causes the change of fate, that it was destined to do in the first place.

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