The spiritual calf must be raised in the altar water, Shi Feiyang asked Huo Wuhai about the Wen Spider.
That Wen Spider was born from a millennium-old scorpion mating with a Fire Spider, producing four hundred and ninety-one eggs in a single birth. Upon landing, they burrow into the soil, sinking an inch deeper with every clap of thunder, and after three hundred and sixty-five years deep underground, nurtured by the damp and hot airs of earth's poisons, only then can they take shape.
Once born, the young spiders consume each other. Eating a head makes one's own head larger, eating a leg makes one's own leg grow. By the time the last one remains, with each thunder, it ascends an inch until it emerges to the world.
When it has fully emerged, it possesses divine skills, able to grow large or small, and even nurtures an inner core in its belly into a fire spiritual pearl. With the passage of days and years, even immortals and Buddha find it difficult to control.