They acquired a variety of different abilities. Some people's abilities, once awakened, would transform them into powerful half-human, half-beast monsters; these were called beastized warriors. Others could partially transform their bodies into plants, gaining certain special abilities of plants. Because extracting Intelligence Source from plants was extremely difficult, and the dosage even harder to control, this type was very rare. These warriors were called plantized warriors. There was yet another type: the psychic warriors.

Some people, after undergoing forced transformation with large doses, did not experience physical mutations, but instead developed extraordinarily powerful mental abilities. They could either use their psychic powers to launch direct attacks, or communicate with certain elements in nature and unleash powerful, unpredictable assaults through them. Because they used mental power, they were called psychic warriors.

The human brain is the most fragile part of the body, known as God's forbidden zone. Many people, due to excessive dosage and unchecked growth of mental power, became idiots. Moreover, it is said that scientists have never determined why Intelligence Source can so rapidly boost mental power. Thus, this type of person was the rarest, but also the most formidable, becoming the trump cards of war.

Because their abilities were their greatest secret, once discovered by others, their weaknesses could be exposed to the enemy, which was extremely dangerous. Since they used Intelligence Source to transform themselves, they generally called themselves Intelligence Source warriors. However, after the war ended, these titles gradually faded away, and people began to refer to those with special abilities as espers.

Intelligence Source warriors had another characteristic: their combat abilities would continuously grow stronger as they fought. However, this growth was not unlimited. When their abilities reached a certain level, they would automatically enter a bottleneck state. If they could break through this bottleneck, their abilities would be greatly enhanced. They called their growth evolution, and the process of breaking through the bottleneck advancement. They used the number of advancements as a mark of their rank within their own type: those who completed their first advancement were called first-rank experts, those who advanced twice were second-rank, and so on. In general, the higher the rank, the more powerful they were.

But if they could not break through the bottleneck, their strength would never improve again. If they tried to force an advancement, it was easy to fail—at best, losing their abilities, at worst, dying on the spot. Therefore, advancement was something every Intelligence Source warrior both loved and feared.

According to records, the person who has undergone the most advancements so far was a soldier named Henry Clark during the Apocalypse War. He achieved great military exploits in the war, killing countless enemies and becoming a model for propaganda. According to current data, in the short ten years after his abilities awakened, he continuously evolved and underwent at least seven advancements, succeeding every time. Unfortunately, as soon as the war ended, this person disappeared without a trace. Among those who remained, the most powerful had only undergone five advancements. Generally, Intelligence Source warriors who completed two or three advancements were already formidable; those with more than four were extremely powerful. One can imagine how formidable Henry Clark was.

Additionally, although these warriors played a huge role in battles against the magical beasts, their numbers were ultimately too few to turn the tide. Ordinary warriors were almost powerless against those magical beasts. Thus, during the war, the government employed another forbidden technology, fusing humans with certain combat machines. At first, only warriors who had been disabled in battle were modified. These modified warriors displayed tremendous power on the battlefield and were called cyborg warriors.

Seeing the tremendous impact cyborg warriors had on the battlefield, later on, they even began modifying large numbers of physically healthy warriors. The existence of large numbers of cyborg warriors became the main force in turning the tide of battle. However, because this modification was too cruel and violated the laws of humanity and human development, it was widely criticized. As soon as the war ended, this technology was sealed away by the government, and cyborg warriors gradually faded from public view.

Intelligence Source also became a taboo, and no one dared to mention the term lightly. It became a field only the Earth United Bureau could touch. After all, to fight the magical beasts, power was necessary, and every year a group of people was selected to become Intelligence Source warriors. Of course, these people were those who, after testing, were most likely to evolve successfully.

However, quite a few Intelligence Source warriors survived the battlefield. Their mutations were genetic, and many of their descendants inherited their abilities. In addition, some underground organizations did not obey the Earth United Bureau and also maintained a certain number of espers and some Intelligence Source. Of course, these people would not be foolish enough to confront the United Bureau.

Basically, all the Intelligence Source warriors who were successfully transformed back then, as well as their descendants, have been closely monitored by the government. Due to their wartime contributions, some joined the military and government based on their merits, while quite a few disappeared without a trace. Some refused to accept restrictions and eventually negotiated with the Bureau, agreeing to help guard the edge of the magical beast forest alongside the military. They lived together and eventually formed a special family known as the Guardian Family, and the place where they lived became known as the Hermit Tribe.