Notable features of the game include the ability to shapeshift between demon and human forms in battle, and a return of the "press turn" battle system from Shin Megami Tensei III: Nocturne. A large difference between Nocturne and Digital Devil Saga is the ability to change equipped skills at will, instead of at level up. Unlike in Nocturne, unlearned skills are not lost forever, which allows for much greater character customization. The game features a mantra system where Macca gained after battle can be used to "download" new mantras at a saving terminal. Atma, gained by devouring enemies in battle, then allows the characters to Master these mantras, imparting new abilities.
Digital Devil Saga was released in 2004 in Japan, 2005 in North America, and 2006 in Europe. The band Etro Anime provided "Danger", the introductory song for the U.S. version of the game, and Houko Kuwashima provided "Pray", the introductory song for the Japanese and European version of the game.
In the Junkyard, rival Tribes fight an endless war; vying for supremacy and the right to ascend to Nirvana. Everything changes when a blinding light interrupts a skirmish between two Tribes. Serph, leader of the Embryon, awakens after the event to find that his opponents have been violently slain. In a pool left behind lies a young girl with black hair.
The people of the Junkyard soon discover the effects of the mysterious light; Tribe members transform into demons, and feed an insatiable hunger by devouring their enemies. Along with this new "Atma" comes another strange power: emotion.
Soon after, the Karma Temple issues a new law: "Devour the other Tribes and bring the black-haired girl to Nirvana." Hostility only grows, as the Tribes renew their efforts with increased hatred and zeal.
The Embryon struggle to defeat the opposition and protect Sera, the young girl, who may just hold the key to everything.
As a human, he uses a handgun as his weapon of choice. As Varna, he is strong against ice attacks but weak against fire attacks. The player is allowed to customize his stats as they wish, leading to a well-balanced character.
In battle he uses a grenade launcher. As Agni, he is strong against fire attacks but weak against ice attacks. His statistics emphasize Strength and Vitality, with a significant weakness in Magic.
Kind and caring, she has a friendly nature toward others. She creates a friendship with the leader of the Maribel tribe, Jinana and has a sister-like bond with Sera. Argilla was present during the fight between the Embryon and the Vanguards at Ground Zero.
He uses an assault rifle when in human form. As Vayu, he is strong against force attacks but weak against electric attacks. He is a well-balanced character with an emphasis on Strength and Magic.
In battle, he uses a sub-machine gun as a human. As Dyaus, he is strong against electric attacks but weak against ailment attacks. He has superior Agility at the cost of Strength and Vitality.
When the Embryon approach Jinana with a proposal to form an alliance against the Solids, she strikes up a rapport with Argilla over their shared sentiments of battle. Though Jinana was once regarded as a fearless warrior and the main source of the Maribel's strength, after she receives her Atma she begins to develop pacifistic beliefs. She agrees to the union, and joins the Embryon on an attack on the Solids' citadel.
During the conflict, she engages in a battle with the leader of the Solids, Mick. However, due to her reluctance to kill un-necessarily, she had not devoured a single person since receiving her Atma, leaving her extremely weak. She is beaten to near-death by Mick, and then her hunger takes over, transforming her into a mindless demon. The Embryon kill her out of mercy, and in her final moments she finally acknowledges Argilla's sentiment of being her "comrade".
After the sky is shown, Serph wakes up revealing he was dreaming of the sky. He sees that the pod is gone and that a crater was left in its wake. Inside, an unconscious, naked girl is surrounded by white light. With the battle seemingly over, the Embryon take the mysterious girl and return to headquarters.
They defeat Harley’s men (who transform into demons as well) and Serph and Heat eat their remains. Argilla is disgusted by this but Heat reminds her that they need to feed on demons to survive and that it’s “eat or be eaten.” They chase Harley through his base finally cornering him. He seems to know nothing about their transformation or Sera. Harley soon transforms himself into Hayagriva and battles the three of them. The Embryon defeat and kill Harley, gaining his tribe's land for their own as per the law of the Junkyard--to the winner, the spoils.
Back at the Embryon base, Cielo is being chased by a demon, (Vayu) whom the dreadlock-sporting says is Gale. The Embryon don’t know what to do, but Sera comes in (dressed in an Embryon uniform) and sings, soothing Gale and allowing him to turn back into a human. Gale soon questions her about her power but she says that she doesn’t know who she is or where she came from. All she knows is she came to help everyone with their newfound power.
Angel talks with a female voice and orders the tribes to defeat one another and ascend from the Junkyard to Nirvana. Only the last tribe standing is permitted to leave the Junkyard. The leaders point out that this is nothing they haven’t heard before. Angel then tells them that they must also take the black haired girl with them to Nirvana (presumably Sera). She is unique in the Junkyard as no one else has black hair. As well, she has no demon form and can quell other demons with her singing, curing their hunger for other demons (for a short period of time). When Angel notices Serph, she goes ballistic and appears to know Serph from the past. Angel then leaves, reminding the leaders of their goal.
Back at the Embryon base, Gale suggests allying with one of the weaker tribes in order to ensure that neither one is defeated by a larger tribe. He then points out the rivalries that exist between the six tribes. The Embryon and Vanguards were until recently, rivals. The Maribel and the Solids are rivals. The Wolves and the Brutes (the two strongest tribes) are rivals as well. Even after gaining the Vanguards troops, the Embryon are still the weakest tribe in the Junkyard.
Gale suggest allying themselves with the Maribel against their rival, the Solids. Serph, Argilla and Heat once again go together to the Maribel base. They meet with their leader, Jinana. Jinana says that if they can survive getting through their base alive, then they will consider an alliance with the Embryon.
The two groups invade the Solids base from the back. Serph, Argilla and Heat are still together at this point. They proceed inside ahead of the Maribel. Far into the base, the Solids reveal that Bat betrayed his tribe and tipped off the Solids about the surprise attack on their base. The Embryon arrive at the other side of the base to find that a bloody battle between the Maribel and the Solids has taken place with the Solids as the apparent victors.
The Solids leader Mick is beating up Jinana. Jinana is weak from refusing to devour other demons and is losing control of herself. Mick promptly leaves to devour other demons, leaving the Embryon to fight Jinana in her demon form, Usas (more commonly spelled, Ushas). Jinana is defeated and dies an emotional death in the arms of Argilla. After the scene, the camera pans up to reveal Bat watching his leader's death.
The three Embryon member arrive back at the Maribel base to find it under attack by the Solids. Gale is there with other Embryon members to help the Maribel (who are now under control of the Embryon). Gale joins the three of them and proceeds into the Maribel base once more. They find Bat inside and battle him again.
He reveals that the attack was a diversion to allow Mick to kidnap Sera for the Solids. The Embyon soon fall back and arrive back at their base. A beaten up Cielo is found inside and he tells them that the Solids have taken Sera to Point 136. He is told to stay behind at recover from his wounds.
They find Sera, Mick and Bat at the top of the base. Bat stabs Heat and encourages him to betray the Embryon and kill Serph as he will have Sera all to himself (it’s implied throughout that Heat is in love with Sera). Heat fights Serph but it appears to be a fake fight, which Serph loses on purpose. Heat tries to take Sera back from Mick, but Mick holds Sera near the edge of the tower, forcing Heat to back down.
Unable to watch any more, Sera commands Mick to drop her, in a voice that reverberates through everyone present. Bat catches her in his demon form, but reveals that he plans to betray Mick as well and join the Brutes, the strongest tribe in the Junkyard. Before he can make his escape, a bolt of energy severs his wing and he falls into the moat. Cielo arrives in his flying demon form (Dyaus) to catch Sera. Mick quietly tries to make his exit but is stopped by the Embryon. They battle Mick in his demon form (Rahu) and kill him.
Sure enough, Bat is tricked into thinking that Argilla is Sera (as he has to look at her from a distance). The leader of the Brutes is there as well, Varin Omega. When Bat address’ him by that name, he chokes Bat and tells to call him by his proper name, Colonel Beck. A flashback then take place showing Angel talking to Varin at the Temple. Varin claims to know who Angel really is and who he really is. Angel is intrigued but reminds him that the same rules apply to him as they do to everyone else. Varin says he’s not falling for promises of Nirvana. Angel says that Sera is very important and that she’ll release him from the Junkyard if he can bring Sera with him. She gives Varin some sort of power (off camera) and he walks away somewhat satisfied.
The flashback ends and Varin tells Bat not to fail him or else. Serph and the others set bombs throughout the ship successfully. Meanwhile, Argilla battles Bat inside the ship after being tricked into thinking she’s Sera. Argilla is angry over how he betrayed his comrades but Bat seems indifferent to this. Bat manages to get the upper hand and defeat Argilla. Before he can devour her, Serph and the others arrive. They battle Bat and leave him unconscious on the ship. He wakes up just in time to feel the explosion that destroys the ship, the Brutes inside and himself.
The rest of the Embryon arrive and learn that the Brutes have forced the remaining members of the Solids to join them. They start to point out that the rules that they followed even without thinking in the past are breaking down since acquiring the atma. The Brutes shouldn’t be able to force the Solids to join them because they did not defeat their leader. Bat shouldn’t have been able to betray the Maribel, either. Finally, when questioned about what he would do if Serph was killed, Heat replies that he would take over the Embryon instead of allowing them to join another tribe.
Gale believes that it has something to do with the tribes feeling emotions when they previously felt nothing. During their conversation, they're interrupted by a member of their tribe. He says that the leader of the Wolves has shown up from the sewers of the former Vanguards base and is surrendering.
As they follow them, he tells stories of a dream he had where he had a small human who called him “father” and that he called the human his “son.” Gale remembers how he had similar flashbacks of a woman who was crying (he’s been having these flashback throughout the game). Lupa says he’ll go up ahead and clear away the Brutes in the sewer.
At first appears that Lupa is purposely leaving them alive as the Embryon catch up to him. However, their deaths become more gruesome as they progress, suggesting that he’s losing control of his demon form. The Embryon arrive at the sewer ladder that leads to the Brutes base. Before they can leave, Lupa comes in his demonic form (Cerberus), out of control and they battle him.
He’s left mortally wounded and Sera tells him that "you can’t resist eating other demons forever or else you’ll lose yourself". Lupa tells Gale and the others to devour him. Gale asks what he should tell his son if he should meet him. Lupa tells him to tell his son to grow up to be a man of honour. He then says that he’ll be carrying an olive branch. As Lupa dies, Gale feels emotion for the first time, cursing the being who gave them this demonic power.
The Embryon proceed through the mansion and find Varin inside. He begins to fight them (as Ravana) and says that he can’t believe that they would follow Serph after what he did to them. What he did is unknown. Varin fights them and uses a power that causes the Embryon to lose themselves in hunger (presumably, this is how he managed to kill all of the Wolves). Sera is able to cure them of this, however. They defeat Varin and he is angry that they won’t call him Colonel Beck. Varin says that they are all reincarnations of people who have died and what lies beyond the Junkyard is not Nirvana, but the real world. He then mutters that Sera is the devil and that she will kill them all.
He dies and the war in the Junkyard ends. Sera quietly slips away and it is presumed that she is heading for the Karma Temple (they are supposed to ascend the Karma Temple with Sera after defeating the other Tribes). The rain that has been falling since the start of the game suddenly stops as well.
As they walk along the last set of stairs, Sera calls is shown at the top calling out to Angel. She also has a demon beside her that she’s controlling. Angel comes in a flash of light. She appears to be the women that Gale saw in his flashbacks. Sera says she’ll go back with Angel if the Junkyard is left alone and threatens to have the demon kill her if it is not done.
Angel is impressed at her ability to control demons but then summons a glowing green sphere that is able to disseminate the demon into data. She then proceeds to the same to the Junkyard. Slowly but surely, the Junkyard is being eaten, disseminated into data and disappearing altogether. The five main Embryon members are the only ones at the Temple. Everyone else in the Junkyard is being deleted. Sera begs Angel not to delete the Junkyard and that she’ll go with her quietly.
The five Embryon members arrive at the top of the tower and Gale recognizes Angel as the women he saw in his flashbacks. Angel says that she was planning on taking them with her, but plans have changed. They proceed to rush Angel, but Sera freezes them at Angel’s command (in mid running). Sera says goodbye to them and proceeds to an altar with a glowing light that presumably leads to the real world.
Serph and Heat break through the freezing implemented on them. Sera tries to alter gravity and suck them to the ground now. Serph is able to break free of this and transforms into his demonic form. Sera loses control and Serph attack Angel. She transforms into her demonic form (Harihara) and the final fight begins. Angel transforms throughout the fight. She appears to be a normal demon, until she grows to monstrous proportions.
Regardless, the Embryon defeat her. Angel is shocked and Serph attacks her once more. She summons the glowing sphere to defend herself, but Serph shatters it, sending him flying to the other side of the tower. Angel says that the Junkyard is all going to be deleted now and that nothing will stop it. They Embryon proceed to the alter and Gale helps Angel to the altar as well. Angel recognizes Gale and takes his hand.
The Embryon are waiting for Serph to get to the light, but the tower disinigrates before he can get to the altar. Sera screams and the entire tower explodes before any of them can reach the light. The seven of them are left floating in a void of light. Serph tries to reach Sera, but he can’t quite make it. Sera says she’ll find Serph and he nods in response. They are separated from each other and are enveloped in white light, leading to the game’s credits.
Expel and Death Magic
Status Magic (positive or negative)
Other attributes present in the game are physical and "Devour" attacks, which are not classified under magic.
Boasting well known and experienced voice actors, the English voice cast was very well received and added to the popularity amongst many English speaking fans.