Spring Egg Gu

Spring Egg Gu has the size and appearance of white goose eggs. This Gu just like an egg, can only be used once, so it is a one time expandable Gu with the ability to form a small scale Spirit Spring. This Gu once it is placed deep underground will form the eye of the Spirit Spring, which will then obviously become a Spirit Spring. Once a Gu Master does this, the spurting spring water will loosen the soil around it and the mouth of the spring will gradually grow. But the force of the is not enough the height will slowly reduce. In four to five days, the Spirit Spring's mouth shall form and then the Spirit Spring's water will start to flow and then it shall spread to the soil. THen after all this, in several months, the dense Primeval Energy will then turn into the first batch of Primeval Stones. A small scale Spirit Spring can produce at least a hundred million Primeval Stones from the time it formed to the time it ended.

Disadvantage
The Spring Egg Gu has a ridiculous demand on Primeval Essence to be used. How ridiculous it is? Even a rank 5 upper stage Gu Master will have to deplete all of his Primeval Essence to use it, meaning only a rank 5 peak stage don't have to worry about the cost of using this Gu and it also means that among rank 5 Gu this is one of a high difficulty.

Trivia

 * This Gu can only be obtained by killing certain Eggmen or strong Eggmen Emperor.
 * Spring Egg Gu's price is over a hundred millions Primeval Stones. Gu Immortals would buy this Gu from time to time to plant it in they're Blessed Land to have a natural supply of Primeval Energy for every living being in the Blessed Land.