Onion Core
The Onion Core is a ten-layered core whose risky seal-breaking turns a disastrous gacha purchase into the power source of Yeorum's sword.
History
Six opened layers
Yeorum obtains the core during a high-stakes artifact gacha. Each of its ten seals offers only a twenty-percent chance to raise output at first, while failure destroys the core. Gyeoul opens the first layer, after which Bom reluctantly takes over and succeeds five times in succession. The sixth opened layer leaves the core close to three times its original output, reversing Yeorum's financial loss and creating a rare joyful memory for the sisters. (Chapters 314–316)
Fully unsealed and weaponized
By Yeorum's rematch with Simon Abkarian, all ten layers have been opened and the core has reached a 6.2-fold output multiplier; the intervening openings are not depicted, leaving their opener unknown. Yeorum embeds it in her longsword and uses that amplification to overcome Simon, but discovers that a high-output Onion Core also agitates the wielder's emotions. After training herself to endure anger and provocation without surrendering control, she can release its full output without the immediate violent impulse that accompanied her earlier use. (Chapters 336–343)
Forged into Yeorum's sword
The enhanced core is later embedded in Yeorum's Level 3 sword artifact. Because its mana is foreign to her own, she must tame and synchronize it rather than treating the increase as effortless power. Once integrated, the core lets her weapon contest the pressure of Javier Karma's higher-level Sword of Ra and remains part of her mature fighting equipment. (Chapters 385–386 and 434)
Abilities and properties
- The core begins with ten seals, and each successful opening increases its current output by twenty percent; the gains therefore compound. (Chapters 314–315)
- Five consecutive openings after Gyeoul's first success leave six layers open in total and bring output close to three times the starting level. (Chapters 315–316)
- With all ten layers open, the multiplier reaches 6.2 times; at this level the core can disturb the wielder's emotions and encourage violent impulses. (Chapters 336–343)
- When embedded in a weapon, it supplies powerful foreign mana that the wielder must learn to control and harmonize with. (Chapters 385–386)