Although the Goibniu Familia is a smith type Familia, they also handle construction requests as seen when Hestia asked Goibniu to remodel their home. Even though they're not as large as the Hephaestus Familia, their skills are around the same level. Ais Wallenstein and Tiona Hiryute have the Goibniu Familia care for their weapons.
The Goibniu Familia Home is known as the Three Hammer Forge (三鎚の鍛冶場).
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