During the four days, they prepared only the sword's blades, each with different material or using varied techniques. Volig and Shingi were in unknown waters, as they had never made one to have a spirit in it, as they never had access to a Spirit Child before.
They had to test to see what would make the perfect 'body' for it so that there would be no leakage as with the seashell it currently was at.
Fortunately, there was a way to test it: for Shingi to use his Spirit Element. Of course, he couldn't make a Spirit Child, but it mostly seemed to be made of Spirit Element. But there was something else that gave it the spark of life. Still, Shingi was sure that just using his Spirit Element would be enough to simulate it.
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