The largest nation by far, the Dragon Empire (ドラゴンエンパイア Doragon Enpaia) is a military nation whose ruler is unknown.
Dragon Empire holds a longstanding rivalry with United Sanctuary, doubtless due to their closely situated countries. Recently, the Narukami, led by Dragonic Kaiser Vermillion, have emerged from behind the scenes in order to quell the chaos that emerged from the empire after a mysterious force caused the Kagerō to become sealed away. They have been successful in keeping the chaos from degenerating, and now carry the great expectations of the Dragon Empire.
The names of clans from the Dragon Empire are derived from air-based weather.
Secret treasure of Dragon Empire and stories lost in translation
"Dragon Empire", the empire of dragons. With the greatest territory and the longest history of all nations in Cray, there are many secret treasures and stories which could harm their own users, like "the forbidden spell that turns life force into power" and "the Dragon Emperor's blood that grants power at the cost of one's own soul". The stories about these secret treasures, for unknown reasons, are misrepresented in a way more favourable to their users when they are passed to their neighbouring nation(s). Basically, they are described without mentioning the risk. "Obtaining awesome power at no cost"---many captured treasure hunters and gravediggers are those lured by such nonsense.
Life and Death ~Lifespan of Dragons and Humans (A researcher's record)
Dragons, humans, elves, demons...there are various races on planet Cray. Among them, dragons and humans are the majority of Cray's living residents, and according to data, nations with these two races show higher culture levels than other nations. Let's keep that aside, this time, the lifespan of dragons and humans---the borderline between life and death is recorded. The average lifespan of humans (death by natural causes) is about 100 years old, in the last two millenia. However, thanks to modern development of magic and science, it is possible to extend lifespan for hundreds of years (though there are exceptions, most recipients of lifespan extension grow drastically slower after receiving the treatment). Contrastly, pure dragons are not limited by lifespan. The death of dragons mean they lose their vessels, that is, "when their bodies are damaged to a level that cannot be restored", or "their mana dry up for some reason". Due to "different lifespan", humans and dragons---the dragon knights of Dragon Empire, our empire, are fated to separate sorrowfully one day. This is why, they want to believe. The legend that humans who share thoughts with dragons strongly are reincarnated into dragons after death...
- United Sanctuary and the Dragon Empire used to be one Nation known as the Grand Sanctuary. However, after a civil war, the country split into those two Nations.
- Besides Booster Set 7: Rampage of the Beast King, every Booster Set has at least one Dragon Empire clan included in it.
- Every clan in Dragon Empire have their name written by Hiragana, instead of Katakana.
- The Dragon Empire Branch in the anime is dedicated to spreading the fun of Vanguard, which is the opposite of the lore, where the nation is depicted as militaristic.