Undertale Au: FractureTale
💡 Core Concept:
Long ago, a mysterious celestial event called the SOUL Fracture caused every monster’s SOUL to crack—splintering their essence into supernatural "Fragments" that grant each individual a unique power, now called Fracture Abilities.
The underground is now divided between those who embrace their powers and those who fear them. Frisk falls into the Underground at a time when tensions are reaching a breaking point.
🧬 Power System: Fracture Abilities
Fractures are like shards of the original soul traits (Kindness, Justice, etc.) but mutated over time. Everyone has a unique ability related to their fractured trait—but it comes with a personal cost.
Sans – Fracture: Timeline Drift : Can teleport and shift micro-moments in time.
Cost: Each use physically exhausts his body’s lifespan.
Toriel – Fracture: Hearthbound : Create shields from emotional memories.
Cost: Each use makes her forget a cherished moment.
Undyne – Fracture: Piercing Pulse : Launches energy spears that target weakness.
Cost: The longer she fights, the more her senses blur.
Alphys – Fracture: Neural Spark : Control and manipulate energy patterns in machines.
Cost: Her own thoughts get scrambled with code.
Papyrus – Fracture: Unbreakable Frame : Can withstand anything.
Cost: He can’t feel pain or emotions while active.
Flowey – Fracture: Soul Leech : Can absorb fragments of others’ powers.
Cost: Each use chips away his identity, turning him more monstrous.
Frisk – Has a pure SOUL, untouched by fracture.
This means they can mimic fragments temporarily—but if they copy too many, their soul begins to splinter too.
🏙️ Underground Society:
Monsters are sorted into three classes:
Branded – Monsters with powerful, unstable Fractures. Feared, often exiled or hunted.
Bounded – Monsters who suppress their Fracture powers using inhibitors.
Freed – Those who believe in embracing their Fracture and fight for freedom.
The society is tense. Magic has turned into superpowered warfare, and leaders like Asgore believe Frisk’s pure soul can "repair" the Fractures—or weaponize them.
🔥 Themes:
Power with consequence – Every ability has a cost. It’s not about how powerful you are, but how far you're willing to go.
Identity loss – Monsters slowly change the more they use their powers. Are they still themselves?
Control vs freedom – Is it safer to suppress power, or to wield it with intention?
🌌 Story Arcs:
The Fall
Frisk arrives, mistaken for a threat or a savior. Encounters Sans, who warns them not to trust either side.
Branded Uprising
Frisk is caught between the Bounded Enforcers (led by Undyne) and the Branded underground (led by Flowey and Mettaton). Alphys offers a temporary Fracture-copying device for survival.
Memory Wars
Toriel, Asgore, and Gaster reveal secrets about the origin of the SOUL Fracture. Frisk learns the price of their mimic powers.
Soul Collapse
Frisk begins splintering—echoes of the monsters they’ve copied appear in their mind. The final choice looms: repair the system… or shatter it completely.
💀 Final Boss Concept: Fractured Frisk
In one route, if Frisk copies too many Fracture Abilities, they lose themselves and become a multi-ability entity—a fractured version of themselves echoing everyone they've met.
This is all I’ve got so far, still thinking of Asgore’s character for this au, maybe I’ll turn this into a story.
