Life Stream, in short, is the source of life.

It can be known from the Bungenhagen Observatory in Cosmo Canyon that after death, every living thing on the planet will return to the planet and become a part of it. "Spirit returned to the planet, and other fusion, and then flow in the planet. They merge, converge, and then separate, becoming an undercurrent, called the' River of Life'. The river of life ... in other words, it is a soul energy flowing throughout the planet. " (The above text is taken from the script translation of Atian's elder in the appreciation of this site's notes.)

This text vividly illustrates the origin of Life Stream, which is a stream of spiritual energy, and what she flows is the spiritual power of all the dead life on this planet that has not been reborn. After life dies, its body will be decomposed and eventually become the nutrient of the earth; And their souls will return to the planet with the disappearance of their own lives and become a part of Life Stream. And the birth of every new life needs to get its own soul from Life Stream. Life is constantly going round and round on the planet in two ways, one is material (we don't analyze this situation at all here) and the other is the cycle of life.

Life Stream is the life energy of the planet. When she was in prison, Aeris once said that Cetra could communicate with the planet, and when she was a child, she also sensed the news that her adoptive mother's husband had died. These situations show that Life Stream actually has its own consciousness, that is to say, Life Stream is actually the spiritual energy of dead creatures and the gathering of their souls. Therefore, Life Stream is actually divided into two parts, one part is pure spiritual energy, which provides life energy for new life; The other part is the soul of the planet, the dead creatures, who have their own pre-existing knowledge and memory souls, and bring them into the soul of the planet, that is to say, they are integrated with the planet. We always regard this as a whole, and we will not deliberately separate it below. Of course, we will explain it when we need to consider it separately.

Life Stream belongs to spiritual energy, so it may be used as energy. After the research department of Shenluo discovered this situation, it came up with an idea of using Life Stream energy as usable energy. They began to study ways to realize this idea, and finally they succeeded. The result of success was the emergence of magic energy. They built a device called Magic Furnace, which can forcibly absorb the energy of Life Stream from the earth, and compress and refine them to become a kind of energy that can be directly used. The result of this is a seemingly inexhaustible and quite clean energy source, but at the same time, it also creates a situation that this compressed and refined Life Stream energy actually only extracts the spiritual energy in Life Stream and gives up the soul part as residue (because this part cannot be used as energy). Therefore, this refined Life Stream cannot return to the planet to participate in the cycle, because it has no soul and has become an ordinary energy source. If this continues, the final result will be the exhaustion of the planet's soul, and the creatures on the planet will gradually become extinct because they can't get enough soul supplements.

Therefore, if the magic energy is allowed to continue to be used in this way, the planet will gradually go to destruction. But most people don't know this. They don't even know where the energy they use in their daily lives comes from and what is going on. Even most researchers in Shenluo don't know this. Only some people who realize this and leave Shenluo know this, but they can't change anything themselves, and they can only hope on the heroes (of course, I won't say who the researcher is here =v=).

The part precipitated by the previous refinement, because it gathers the knowledge and wisdom of ancient species (the components of the soul) contained in Life Stream, can easily get in touch with the planet and use the power of the planet when using these dregs. This supernatural ability is called magic, and these dregs that can guide people to use magic are called magic stones. Because of the different contents, there are many forms of magic stones, and the functions of different forms are different. Some can directly use the power of the planet as an attack means, and some can guide the power of life in their own bodies to strengthen their combat effectiveness, and so on. Because this rarely happens in normal circulation, there are very few magic stones in nature. Of course, it does not rule out the occurrence of some special cases. In places where Life Stream is particularly rich, some natural magic stones (such as big holes) will be produced because the concentration is too concentrated, but this situation is not very common after all, because it is rare for Life Stream to be over-concentrated.

Of course, the condensed and refined Life Stream is still life energy, so when it is injected into a life, the life will get more life energy than before. In this way, the vitality of this life will be stronger than other lives, which is equivalent to getting more life energy than other same lives in the process of reincarnation. That is to say, if it is in a proper amount, this method can really improve a person's life activity. This improved vitality is reflected in human beings, that is, the improvement of tenacity of physical strength, judgment and vitality. Based on this theory, therefore, Soldier of Shenluo is injected with magic energy, and by this method, their physical fitness is forcibly improved, so as to achieve the goal of super soldiers.

Because of the success of Soldier's manufacturing (at least there are no adverse reactions on most Soldiers), the research department of Shenluo has made a study to increase the dose of magic magic magic, and prepared to train soldiers who may be stronger than Soldier in this way. However, the strength of human body structure is limited, and it is easy to damage tissues and organs when suddenly accepting extra energy from the outside (the system is overloaded and the equipment is burned =v=), and only the human body is in good health. But after all, there are a few people who can become Soldier, which is far from enough for Shen Luo. Therefore, they began the experiment of magic cultivation for ordinary people. The experimental method is not direct injection, but by exposing them to high-intensity magic energy, let their own bodies slowly absorb magic energy, and through this gradual adaptation method, they can avoid being unable to bear magic energy. However, because of the fragility of human body structure, exposure to high-intensity magic coffin will also cause discomfort to the body, so almost all of these humans have mutated, and these mutations are quite rapid because of the existence of magic coffin (after all, magic coffin is a life energy source, which is equivalent to providing a catalyst for their mutation for variants). However, the fragile body structure of human beings can't adapt to such fierce variation, so it will bring unbearable pain in the process of variation, and their spirit will be chaotic under such physical pain, and eventually their minds will be destroyed by pain and become vegetative (the so-called deep magic poisoning, of course, Cloud is just the same symptom), or they will become animals that only know killing and destruction. This is the beginning of the Nibelheim incident.

Perhaps because of the failure of this experiment, Hojo did not continue the study of magic injection after that, but changed to the study of Jenova cell transplantation. However, this experiment also revealed a problem, that is, the magic pill can accelerate the metabolic system of organisms, because almost all the subjects involved in the experiment have a great degree of variation, so it is possible to use the magic pill as a nutrient solution for cultivating new species (sweat, I can't think of other words for the time being), so his new subjects will be soaked in the magic pill.

Here, we need to explain the Magic Pupil. The Magic Pupil is an extraordinary light in the eyes because of the injection of Magic Pupil, which has much higher life energy than other human beings. This is because there is extra energy in the body that is not really your own. However, it is not only the injection of magic pills that can make the pupil of magic pills appear. Anyone who comes into contact with Life Stream with too high concentration may receive some extra life energy. Because the magic coffin is actually the energy embodiment of Life Stream, and the pupil of the magic coffin is only the direct embodiment of the extra life energy in the body, so the nature of the two is the same-that is, the eyes. This extra energy will be reflected in the eyes, so the eyes of people with magic pupil usually glow with green light, which is the color of magic and the color of Life Stream. So it can't be distinguished from people who are exposed to high concentrations of Life Stream, because the color of Life Stream is also green. That's why in the Nibelheim incident, they can also see the magic green in Cloud's eyes, because before that, they passed a place full of high-concentration Life Stream (remember that natural millstone? ), and it is precisely because of this that Sephiroth misunderstood the identity of Cloud and overestimated God Luo's concern about this matter (if an ordinary Soldier is a member of Soldier, the importance attached to this matter is self-evident), so he will not hesitate to jump (the reason for jumping is described in detail in another article, so I won't repeat it here).

As we said before, Life Stream itself is not only a part used as energy, but also has its own soul, which is actually the soul of the planet. In Ifalna's memory, the soul of the planet is quite powerful. She can control Life Stream, use the energy of Life Stream to make weapons, and even communicate with Cetra at the language level, which is almost a complete intelligent life. But in the game, we can't see this at all. The planet is completely defenseless by the magic furnace of God Luo. As Cetra, Aeris can only feel the plaintive cry of the planet, and even when she comes into direct contact with Life Stream, she wastes some time to understand each other's meaning. All this shows that the present planet is completely different from the original planet.

so what causes the weakness of the planet? It is necessary to mention Cetra here.

Cetra is an intelligent creature who has lived on this planet since ancient times. They are very close to human beings, and they are almost identical, except for one thing, that is, Cetra's ability to contact and drive the planet is completely incomparable to current human beings. They can influence the behavior of the planet through their own will, and even use it to drive the flow of Life Stream (in short, it is very powerful =v=). Of course, after their death, they will also participate in the life cycle of the planet. Whether it is life energy or soul, their knowledge and wisdom will be left in the Life Stream, and even their consciousness. As a Cetra, they love the planet more than anything else, so it is quite noble for them to participate in the cycle of life after death and become a part of the planet. So there is the legend of Promised Land, where Cetra will go after her death, which is a place full of happiness. In fact, this Promised Land is Life Stream. There, the life energy of the dead Cetra will participate in the cycle, but their knowledge and wisdom will stay, with the souls who have not yet participated in the cycle and with the planet. And why Promised Land is a land full of happiness, let's discuss it below, and let's leave it alone for now.

With the passage of time, although the souls in Life Stream have been circulating, the extinction of Cetra has led to fewer and fewer souls that can really blend into the planet itself. Although many souls of Cetra were still preserved before, these ancient souls gradually lost their vitality because of too much time, leaving only their own knowledge and wisdom. They are just like the guardians of ancient temples. Although they still have their own knowledge, they even forget how to talk and communicate. That is to say, the planet now actually has only an aging soul. Therefore, when Shen Luo collected a large number of lifestreams, the planet was almost completely helpless except for a burst of mourning; As Cetra's Ifalna, she once said that she can't hear clearly what the planet wants to say now.

But the arrival of Aeris changed all this. When Aeris died, she was using the white magic stone to communicate with the planet. The forgotten city itself is a place full of Cetra's memories, which means that the soul of the planet is the most concentrated place, and one of the functions of the White Magic Stone is to be able to directly contact with the soul of the planet. Therefore, in this environment, Aeris did not simply merge into the Life Stream as usual after his death, but directly entered the soul of the planet. Because she didn't pass the classification of Life Stream, she not only kept her knowledge and wisdom before her death, but even her memory and personality were preserved (other Cetra, such as Ifalna, just returned to the planet normally because they died under normal circumstances, so it didn't have much impact), and the soul of the planet was supplemented with such vitality, and it soon came back to life. With her vitality, Aeris quickly merged with the planet and played a leading role in the soul of the planet. Therefore, in the end, we can control Life Stream through our own will to increase the power of Holy, and finally kill the meteorite. Of course, this is another story.

In the Nibelheim incident, Sephiroth jumped into the Life Stream, gained the knowledge of ancient species in the Life Stream, and thus knew the method to control the energy of the planet. Therefore, when Aeris started Holly, he stopped the start of Holly with his own strength. At the same time in order to avoid