|“||Can't you see that death lies in wait on your path, ready to consume all hope?||„|
Shin Megami Tensei
Lucifer is the Chaos alignment, which associates with freedom and war. The protagonist can choose the Chaos alignment for freedom of choice, thoughts and actions. However, this freedom would lead to a vast amount of suffering and anarchy, leading the world into a primal state of unsuppressed vice and survival of the fittest.
Lucifer later takes the name of Louis Cyphre. The protagonist finds him after the Great Destruction, where Louis Cyphre observes the protagonist's actions. He hints at a much greater knowledge of what is happening, and seems to make allies of many demons quite easily.
At the end of the Chaos alignment path Lucifer appears in his true form to offer his congratulations to the protagonist for defeating the God of Law and resurrecting the old gods, but warns that the "true enemy" still exists.
Shin Megami Tensei II
In Shin Megami Tensei II, Lucifer is a well-respected figure amongst Demons. He is detested by YHVH and angels and he hates them in return. Lucifer represents the Chaos Path, where emotions are over cold logic, in 'purpose justifies the means'.
Throughout the game, Lucifer is aware that Aleph, the protagonist, is part of the Messiah project, and thus, many demons under his commands would assault him. As the game progresses, Lucifer becomes intrigued by Aleph's ability to defy God, and wonders if he is the incarnation of Satan, the one who would Judge them all. Lucifer is later disappointed to learn that Aleph was not Satan, though Lucifer himself could sense the imminent signs of Satan's coming.
Since Satan was sent by YHVH to cleanse the demon world, Lucifer, as the lord of the demonic world could not bear to see it's destruction. He offers Aleph an alliance to face Satan and finish their battle once and for all. Should Aleph chooses the Chaos Alignment path, Lucifer will join him in order to help protect the denizens of the world from Satan's judgment upon the world.
Shin Megami Tensei III: Nocturne
Lucifer plays an important role in Shin Megami Tensei III: Nocturne, where he takes the form of a young boy and an old man. They are accompanied by an old nurse, and a young woman dressed in black mourner's garb respectively. Assuming the form of a child, Lucifer is first seen in Shinjuku Hospital, where he is intrigued by the protagonist, Naoki Kashima, but disappears when the protagonist approaches him. After the Conception, to allow Naoki survive in a now demon-ridden world, he places a Magatama into Naoki, allowing the insect to merge with him to transform him into the legendary Demi-Fiend. As the story progressed, Lucifer would assume the form of either an old man or a child, giving hints about the nature of Conception, and God himself.
Lucifer would play different roles depending on Naoki's actions and the path he chooses. In the Neutral path, Lucifer is reminded of himself by protagonist's decisions, as Lucifer himself walked his own path and chose his own decisions before and after his fall from grace. He warns the protagonist to keep his demonic powers, as one day, the "true enemy" would hunt him down for defying his will, just as what happened to Lucifer himself.
In the updated release of Shin Megami Tensei III: Nocturne, titled Shin Megami Tensei III: Nocturne: Maniax, Lucifer takes a more important role, it is revealed that he resides deep inside the Labyrinth of Amala. He first summons the Demi-Fiend there to grant him the Candelabrum of Sovereignty, and instructs him to hunt down and retrieve the all the other Candelabra from other fiends that were also given them. His plans are finally revealed should Naoki venture into the final Kalpa of the Labyrinth of Amala — Lucifer is planning to create an extremely powerful demon, strong enough to lead the legions of Chaos in a final battle against YHVH. By granting many powerful demons a Candelabrum, Lucifer had planned to see who would reign supreme amongst demons and fiends.
An extra ending, accessible only by completing the Labyrinth of Amala unlocks the 6th ending, the True Demon path. After Naoki kills Kagatsushi, the 2 entities, the young boy and the old man, appear and tell the Demi-Fiend that he succeeded in breaking the cycle of destruction and rebirth, and thus, time itself is dead. The universe has been reverted to it's initial state of primordial chaos, along with all other worlds being finally freed from the grasp of YHVH. This however would mean that Naoki would be forever cursed by the Great Will, but Lucifer comforts by telling him that that demon race along with himself would always bless him. The blond child and the old man then tells Naoki that he needs to test his powers, and the two entities fuse and assume Lucifer's demonic form, engaging Naoki in battle.
Shin Megami Tensei: Strange Journey
Lucifer appears here as a strange girl the Protagonist meets early in the game, calling herself Louisa Ferre. Throughout the game she appears and gives cryptic clues to the Protagonist, and seems to be aware of Jimenez's fate to become a demon and serve the Chaos faction. Should the Protagonist follow the Chaos path, she appears after the Herald Mastema is defeated in Sector Horologium, where she mocks him for his state as a fallen angel. She also proclaims that though she has no love for humanity, she will never abandon them.
Shin Megami Tensei IV
Lucifer is the main antagonist on the law route and the representative of the Chaos faction. Much like his earlier incarnations, he values war and freedom. He is more vocal about his hatred towards YHVH, calling the heroes before fighting them "Puppets of God".