The Azure Dragon is one of the Four Symbols (四象) of Chinese constellations along with Vermillion Bird, White Tiger and Xuanwu. It represents the East, spring, the color azure (green/blue) and the Wood Element. In Japan, it is one of the four guardian spirits of cities and protects Kyoto.
In some official English versions this demon is incorrectly translated as Long due to confusion between Four Symbols (Si Xiang) and four benevolent animals (Si Ling or Ssu-Ling) of China. In the original Japanese version, Seiryu or Qing Long represents one of the Four Symbols and Ryu or Long belongs to four benevolent animals which are fundamentally different.
In MTII, if the player possesses the Heidrun, from trading a Member's Card, and the Fallen Angel Wing, after doing the Jack Frost Jr. trick, the next time the Cathedral of Shadows is entered, Jack Frost Sr. will offer the hero a Qing Long, Bai Long and Kali to add to his team, regardless of level.
Qing Long appears as a field boss within Ueno's Kuchinawa Cave area and as a final boss of the medium difficulty ranking for Hongou field. To obtain his plug-in, players must defeat the illusion that appears in Kuchinawa Cave at exactly 3:00 or 15:00 in-game time. If done correctly, a much stronger version of the boss will appear somewhere within the cave. By defeating it, players obtain the item necessary for his fusion. He is a triple fusion of Jikokuten, Quetzalcoatl, and Gandharva.
Known as Long, he is an optional boss in the Challenge Quest, Slaying the Dragon of the Lake. Found at Lake Mikado near Mikado Castle, he asks if Flynn has come to slay him. Answering yes has him attack and call him a fool for thinking he can slay him. After defeating it, the dragon admits to underestimating him and is surprised by his great power. He asks Flynn if he believes dragons to be "Enemies to be slain for honor and glory," or as gods of the land. Telling Long that dragons are just beasts to be slain shifts Flynn towards Law, while believing that dragons are holy spirits shifts him towards Chaos. He decides to leave the Lake after the battle.
Purchasing the Mikado Wood upper body armor will grant Flynn a resistance to Force attacks during the battle. Fortuna will also absorb Long's Force skills and may be fused with a special fusion of Napaea, Dwarf and Melchom.
"One of the Ssu-Ling, celestial creatures in Chinese lore. It represents the direction east, the season of spring, and the element of wood. It is the noblest of the Ssu-Ling and dwells in a palace at the bottom of the ocean. In Feng Shui, placing water in the east side guides its power and is said to bring good fortune."
—Shin Megami Tensei IV Apocalypse compendium
Long can teach Nanashi the Zandyne and Acid Breath skills through its Demon Whisper. It benefits from learning Force and support skills.
Known as Seryu and Seryuzom, he must first be resurrected as a zombie and then fused with his soul gem to be reborn as Seryu. Seryu has the power Battle Rage, which makes him go berserk against mean foes. Seryuzom can be revived through Relic Fusion using the combos Blood-Slim-Wing, Lion-Fist-Slim or Lion-Dino-Wing. Seryu can perform the combo Freeze Wave with Icy Ace or Warbolt and King Freeze with King Icy.
Known as Long in the game. After defeating Ananta in the final floors of the Karma Temple, the Embryon can come down from the tower and find out that four powerful demons have taken over several sectors of the Junkyard. Long appears in Ajna, in the piano room in the red configuration. The Asura Long is a man who follows the orders of Huang Long. The battle is quite simple as long as Long is not hit by Ice spells, either by the Embryon or his own, as he will greatly healed by them.
Like the battles with the other strong demons, the battle has three stages. Unlike them, however, Long will begin the battle with hard hitting spells. His most dangerous attack throughout the battle is Mabufudyne, so it is imperative the party guards against that above anything else. During the first stage he will typically go a round of casting Makakaja twice, followed by Mind Charge and in the next round will unleash Mabufudyne followed by Revelation. During the second phase he will start using the same pattern but will also use Tarukaja for two turns and Power Charge. The next round will be Revelation followed by more attacks. He will also attempt to heal with Dia in this round.
During the final round he will begin mixing things together. With the Makakaja/Makakaja/Mind Charge rounds and Tarukaja/Tarukaja/Power Charge rounds back to back. He may also use the Rage skill to use Mind Charge and Mabufudyne back to back in this phase, allowing him to deal crippling damage without interruption. He will begin using Diarama in place of Dia to heal himself.
"One of Ssu-Ling, celestial creatures in Chinese lore. It represents the direction east, the season of spring, and the element of wood. It is the noblest of the Ssu-Ling and dwells in a palace at the bottom of the ocean. In Feng Shui, placing water in the east side guides its power and is said to bring good fortune."