The Ouroboros, also known as Ophis or simply Ouroboros, is an ancient symbol depicting a dragon or a serpent swallowing its own tail to form a cycle.
It is a very important religious symbol over the ages. In alchemy, it is a purifying sigil. The myth of the Ouroboros is not dissimilar to other myths of cosmic serpents, such as the Australian Aboriginal myth of the Rainbow Serpent, Ananta Shesha and the Leviathan. The image of Ouroboros crossing itself into an infinity symbol is a modern idea, but one that retains the meaning of endlessness.
"A dragon that signifies eternity. In biting its own tail, it forms a neverending circle. In alchemy, the art of Hermes, it is considered an important material to create the Philosopher's Stone. Some of Ouroboros' aspects are similar to those of Oceanus in Greek lore and the Biblical Leviathan."
—Shin Megami Tensei: Strange Journey compendium
Ouroboros is the end boss of Sector Eridanus and one of the Mothers of the Schwarzwelt. She dwells in the Vanishing Point that acts as the top floor of Eridanus, and (supposedly) the Red Spite's mission would be complete and they could make their leave when she was defeated.
Ouroboros is fought twice; in her first form, she will continually regenerate health and use Wild Thunder, a potent Electricity-type attack, and Disaster Cycle, a light almighty attack against all enemies, which has the added issue of liberally inflicting any possible ailment to the targets. Overall, the first battle is mostly difficult because of her ability to replenish her health.
However, it becomes apparent Ouroboros is simply immortal in this form, forcing the Strike Team to leave; Captain Jack is the one to call the protagonist and point him to the exact locations from which Ouroboros is drawing energy. Once the demons at these locations are dead, Ouroboros will be dismayed about the "torus of eternity" being severed, and enter a second and more dangerous stage when the protagonist again enters the chamber. Chances of seeing Disaster Cycle greatly increase and Ouroboros begins using Wave of Death, a potent physical attack.
Once she dies, she will moan in agony about the "holy realm of the gods" being defiled by humans, and leave behind a band of energy, pocketed by the protagonist, and her rare forma.
After her defeat, the Red Sprite begins to make their leave from the Schwarzwelt while the Joint Project plans to destroy it with a flurry of Nukes. However, before they can make their leave, The Three Wise Men intercept them and openly mock humanity in front of Jimenez, Zelenin and the protagonist, telling them that their efforts are futile and they should get the other Mother's Exotic Matter to change the world instead. They then forcefully strand the Red Sprite in Sector Fornax, opening the second phase of the game where Tiamat and Maya had to be defeated.
Following this event, Ouroboros is unlocked in special fusion using five demons: Dzelarhons, Kwancha, Mandrake, Basilisk and Vouivre, referencing the demons giving her energy.
"A dragon that signifies eternity. In biting its own tail, it forms a neverending circle. In alchemy, the art of Hermes, it is considered an important material to create the Philosopher's Stone. Some of Ouroboros' aspects are similar to those of Oceanus in Greek lore and the Biblical Leviathan."
Known as Urobros, it is the fifteenth boss in the game. It guards the 12th floor of Jerusalem.
Persona 2: Innocent Sin[]
When the party chases Haruo Weyland in the Persona Thief quests, he summons demons to block multiple stairs that lead to him. One of such demons is Ouroboros.
DemiKids Light & Dark[]
"An invincible snake who lives by feeding on its own regenerating tail."
—DemiKids Demonary
Known as Urboros, he can perform the combo Dragon Surge with Kyuki and Dragon Cross with Kaleidos. Urboros also has the power EarthWall.