- "Can it be... you know about Aura?"
- — AI Harald —
Phantom is the twenty-second episode of .hack//SIGN.
Bear, Mimiru, and Subaru leave to meet with the AI Harald without BT, who decided not to join them. To meet with the AI Harald, Bear leads them to a dungeon, following the directions of Helba. In the dungeon, Bear explains what he learned from Helba: that Harald had left some hope or unfulfilled wish in The World and that he left copies of himself to oversee its completion, making himself a being that was everywhere in The World but not in any one place.
Back in the dungeon, Mimiru recalls that this is the exact same dungeon she first met Tsukasa in. Tsukasa himself is still under the effects of Morganna's Data Drain and is sitting in a daze near Aura's bed. Deeper in the dungeon, Bear's party encounters a Data Bug. Subaru falls while attempting to escape. Before the Data Bug attacks her, she is saved by Balmung, who followed them into the dungeon. Balmung tells the three to move ahead while he keeps the Data Bug busy.
At the bottom of the dungeon, the three find the Helba Gate leading to an AI Harald. At first, the AI repeats the same message he told previously, but Mimiru's insistence that he speak about "the girl" breaks the infinite cycle, and the AI Harald asks if they have met Aura.
Having decided that the Data Bug cannot be defeated, Sora escapes battle and leaves the bug to a confused Silver Knight. Silver Knight flees as well and is met by Crim.
The AI Harald finally explains that he created both Aura and a being designed to awaken Aura. Aura was meant to be a daughter, to be the proof that he loved a certain person. The other being he created warped his feelings and is trying to warp Aura. He warns that the current, warped, Aura, must not be awakened, but that there also may be hope if the correct Aura can be awakened. From the AI's words, Subaru and Bear come to the conclusion that Tsukasa was a tool used to warp Aura and give birth to her. Before more progress can be made, Morganna, the omnipresent being that Harald created, interrupts the conversation and deletes both the AI Harald and his field, forcing Bear, Mimiru, and Subaru to flee.
At Mac Anu, Crim consoles Silver Knight, who is still feeling lost. Crim asks why he is still in The World, then tells him that he does what he should do; he says that The World is a game, and that he should enjoy it.
Having escaped, Bear, Mimiru, and Subaru go over what they have learned from the AI Harald. They decide that their enemy has been using Tsukasa to warp Aura and that they should give birth to the correct Aura. Mimiru is excited, but Bear explains that their enemy is omnipresent and that they have no way to fight her. Subaru believes that Tsukasa is the only factor on their side and that he is the key to awakening the true Aura. Somehow, Subaru's yearning for Tsukasa reaches his ears and snaps him out of his daze.
Sora, feeling down that he had to escape from the Data Bug, spots Macha and grabs on to her at the exact moment she decided to return to Morganna's area. There, Sora spots and takes interest in the warped Aura...