Following her transformation, Liadain tracks the newborn Harbinger Yurfaln to an earth house in the Hills district, where it has already begun to feed on a local couple by tricking them into eating its living clay. Driven by a desperate need to survive, Liadain leaps directly into the Wound, a distorted, unfinished hospital hallway where Yurfaln waits. Using her newly manifested tarot cards, she infuses the nightmare with her own toxic green magic, freezing the creature's corruption like frost on a swamp. Yurfaln, a monster born from the dying thoughts of a patient who believed death was a beautiful transition, welcomes the pain and attempts to share it with her. Recognizing that the monster seeks to glorify suffering, Liadain lures the creature into a twisted medical machine of her own design, driving a needle into her own arm to connect their souls. In a brutal climax of willpower, she pulls with all her might, ripping Yurfaln's essence and its rust-red heart directly from its body. The Harbinger crumbles to dust, and Liadain consumes its core, gaining the ability to turn her own wounds into magical fuel. However, the victory leaves her physically exhausted and desperate for vitality. Hiding in the woods, she discovers a terrifying aspect of her power: she can inhale the life force of healthy, sleeping humans, instantly healing her injuries but leaving them with a lingering malaise. Returning to the hospital, she discovers the first permanent mark of her magical evolution when a single strand of her hair turns stark white, signaling that her journey into cosmic horror has only just begun. The encounter forces her to realize that survival demands she become a predator, casting aside the quiet dignity of a patient to embrace the monstrous reality of her new life. As she stares at her reflection, she realizes she must keep hunting to stay ahead of the decay, but how long can she hide her worsening condition from the doctors before they realize what she has truly become?

After being approached by the energetic Keepers Shona and Mide, Liadain joins them under the alias Eyna to investigate a series of mental breakdowns at the Sky's End Tower. As they reach the observation deck, the sky shatters into a kaleidoscope of static, dragging them into the Wound of Irakkia, a massive castle built of concrete rubble and flickering TV screens. Separated from her companions, Liadain is subjected to Irakkia's reality-bending illusions, which try to drown her in a simulated abyss. She resists by focusing on her physical pain, using her cards to infect the surrounding screens and radios with her toxic green mist. When she reunites with Shona and Mide, they discover that Irakkia cannot alter reality within their direct line of sight. Working as a defensive triangle, they protect Shona as she unleashes a devastating storm of red lightning, destroying the lighthouse lanterns that anchor the Wound. In a desperate bid to survive, Irakkia launches a surprise attack, skewering Liadain through the chest. Facing certain death, Liadain's survival instinct flares, and she instinctively drains Mide's life force to mend her own broken flesh. Though she stops before killing her ally, the act leaves Mide weak, terrified, and resentful. Together, they corner the weakened Harbinger, and Shona blasts it into glittering particles. Liadain and Mide attempt to share the heart, but the division is messy, leaving Liadain with the larger portion but denying her the full understanding of the monster's soul. Outside the Wound, Mide confronts Liadain about her parasitic nature, calling her a monster. Devastated and unable to defend her actions, Liadain flares her shadows to drive them away, shattering their brief alliance and leaving her to walk her dark path entirely alone. She retreats to the hospital, her hair now marked with more white streaks, knowing she can never trust another Keeper with the truth of her parasitic existence.

Determined to avoid other Keepers, Liadain ventures into the unclaimed forests beyond New Claris, where she stumbles into a brutal war between local Harbingers. She meets Vianzia, a beautiful but sadistic insectoid queen who communicates through a complex dance. Vianzia uses Liadain as a shield, leading her toward Ourien, a massive dragon-like beast of burning wood, and Esonei, a pathetic, weeping blob of masks that infests Ourien. Esonei attacks Liadain, invading her mind with a torrent of agonizing nightmares and self-destructive impulses. To fight back, Liadain turns her own plague inward, using Yurfaln's blessing to fester her magic to lethal heights and forcing Esonei out. Recognizing that she is caught in a trap, Liadain threatens Vianzia with mutual destruction, flaring her toxic power like a poisonous animal. Surprised and delighted by her audacity, Vianzia retreats and allows Liadain to escape. Before leaving, Liadain unleashes a devastating plague-wind that rots Vianzia's jungle, ensuring the monsters remain too weak to expand. She returns to the city center, only to detect a faint, quiet Harbinger nesting in a local stepfamily's home. She discovers that the family's young son, Brendan, is grieving his dead brother and projecting his spirit through a formless Harbinger egg. After a tense confrontation, Liadain kills the illusion, absorbing its tiny core. This quiet victory yields almost no strength, leaving her to realize that chasing random monsters is a losing game. To survive, she must find a way to study Harbingers, leading her to the university library where she finds a corrupted book titled How to Be the World. Recognizing its potential, she infects the book with her magic, deciding to watch it grow rather than destroy it, embarking on a forbidden experiment that could either save her or doom the entire city.

Liadain's experiment spirals out of control as the book-Harbinger, Aulunla, spreads its copies across the city, prompting its reader Isobel to perform dangerous rituals. After a violent clash with another Keeper named Tetha, Liadain tracks the original book to a self-storage unit, where she triggers its transformation. Dragged into a surreal Wound of crumpled paper, painted clouds, and falling comets, Liadain faces a massive, gluttonous caterpillar that Aulunla has summoned. Burning her stored health to achieve superhuman speed and strength, Liadain dodges the creature's charges and uses her cards to rot the Wound from within. She collapses the ground beneath the caterpillar, sending it plunging into the void. In a final, desperate act of self-sacrifice, Aulunla merges with its creation, hatching into a colossal origami insect that unleashes a devastating beam of pure light. Liadain channels her entire plague into her cards, launching them in a dark spiral that shatters the Harbinger's core. As the Wound collapses, Aulunla's final thoughts echo in her mind, revealing its tragic desire to build a world of color for its friend. Liadain absorbs its heart, gaining the ability to understand the language of magic and Harbingers. Outside, she finds her hair heavily streaked with white and her eyes glowing a permanent, toxic green, leaving her unable to hide her monstrous nature any longer. Confronting her Messenger, she receives validation for her dark path, realizing she must continue to study, cultivate, and break Harbingers from the inside out to survive. As a white-robed Keeper descends on radiant wings to investigate the storage lot, Liadain slips away into the shadows, a pariah who has traded her humanity for a chance to live.