Due to the guarantee of the "light of life" of the "staff of reincarnation", the action of "greening the northwest" was carried out smoothly, Sun Hui first connected the land of Hehuang to the various oases in the territory of Xixia, and then adopted the method of "point to area", based on each "green belt", to expand to the surrounding areas. ◢ With * dream * small ◢.1a

In her spare time to change the environment in the northwest region, Sun Hui often discusses her dreams with Ye Chuchu and Xiao Tiantian, searching for clues about the whereabouts of Wang Linlin and Du Lili.

Up to now, after the separation, the four girls have appeared in his dreams, among which Ye Chuchu appeared in the ancient Roman Colosseum, Xiao Tiantian appeared in the desert of ancient Egypt, Du Lili appeared in the "Jiuchi Meat Forest" banquet of the king of the Shang Dynasty at the end of the Shang Dynasty, and Wang Linlin appeared in the blood sacrifice ceremony of the sun god in Tenochtitlan, the capital of the Aztec Empire in Central America.

Although the content of these dreams is absurd, they all provide a clear era of their "crossing", among which Ye Chuchu and Xiao Tiantian have confirmed that they were indeed transported from the Soviet-German battlefield to these two eras, and from these two eras to the Song Dynasty. Then, Du Lili and Wang Linlin should also be transported to the Song Dynasty from the era that the two Sun Hui dreamed of.

Another important clue comes from Zhang Xubai, a drunkard Taoist with magical prediction ability, Zhang Xubai clearly told Ye Chuchu that Xiao Tiantian is in Western Xia, Du Lili is in Jinguo, and Wang Linlin is in Xiliao. Now that Xiao Tiantian's whereabouts have been confirmed to be accurate, then Du Lili and Wang Linlin should also be in Jinguo and Xiliao.

After Xiao Tiantian appeared, Ye Chuchu had the idea of finding Du Lili and Wang Linlin, after pacifying Xixia, she wanted to go to Xiliao with Sun Hui to investigate, and the ongoing greening work, in fact, to a certain extent, is also to prepare for going to Xiliao - through the last "Devil's City" adventure, she has a deep understanding of the harshness of the desert environment, and wants to make a "green channel" to Xiliao.

Sun Hui, who is familiar with history, knows that although the Western Liao has not officially established the country at this time, under the hard work of the famous general Yelu Dashi, the strength is already quite strong, and it is by no means as easy to deal with the Western Liao as it is to deal with the Western Xia.

Sun Hui probably told Ye Chuchu and Xiao Tiantian about the situation in Western Liao, in the spring of 1125, Emperor Tianzuo of Liao was captured by the Jin army in Yingzhou on the way to flee to Western Xia, and the Liao State was destroyed. At this time, the Liao general Yelu Dashi expected the death of the Liao State and had led the army out half a year ago. Yelu Dashi advanced all the way to the northwest, and arrived at the city of Kedun, where the Northwest Road Recruitment Division was stationed in the northwest of Liao's northern frontier, where he placed officials, straightened out soldiers and horses, sharpened weapons, and obtained more than 10,000 elite soldiers.

Because the city of Kedun is an important frontier town in the northwest of the Liao State, the border army is not allowed to be requisitioned at will, and the army has been preserved in the war, and there are hundreds of thousands of horses that can be ridden here.

After Yelu Dashi seized real power in the city of Kedun, he "raised troops and waited for the time to move". This base area has pastures with abundant water and grass, and is rich in cattle and sheep, which provides the economic foundation for the Yelu Dashi regime. There is a wide desert area in the south of it, which has become a natural defense line, and after five years of recuperation, the strength of Yelu Dashi has been quite strong, so it was decided to develop westward, expand the field, establish a stronger material foundation, and then come to destroy the Jin State and recover the Liao State.

In February 1130, Jerodashi traveled westward. He led his army into the Turkic region of Gilligis in the upper reaches of the Yenisei River and attacked the tribes there, which in turn harassed the army of Jerodashi. Yelu Dashi led his army out of here and headed west into the area of Yizhishui and Yemili River, conquering many tribes along the way, expanding the land to a wide area.

However, according to the information provided by Yue Fei, after learning that the Song army had destroyed Western Xia, Yelu Dashi had stopped his westward expedition, led the army back to Kedun City, and sharpened his troops and horses, and seemed to have plans to return to the hometown of Liao to the east.

After the Song Dynasty restored the sixteen states of Yanyun, the original Liao homeland became a buffer zone between the Song and Jin, the Song Dynasty because of the limitation of national strength, unable to overexpand, is to keep the border carefully, and the Jin State after the destruction of the Liao, the southward invasion of the Song Dynasty failed, the strength was greatly damaged, and it was unable to govern the entire territory of the Liao State, so it only occupied about one-third of the land of the entire Liao territory adjacent to the relatively rich Jin hometown, and the rest of the place was used as a buffer zone between the Jin and the Song Dynasty, only a few generals and a few troops were stationed, and loose management was implemented. At present, most of the areas in the hometown of the Liao State are mostly run by the Khitan tribes themselves, and only a few tributes are paid to the Jin people.

Sun Hui knew that for the Song Dynasty, the current state of Liao and Jin was the most beneficial. But if Yelu Dashi returned to his hometown of Liao, the situation would be different.

Ye Chuchu suggested that Sun Hui lead the Song army to continue the westward expedition, destroy the Western Liao, and solve the problem once and for all, but Sun Hui did not agree, he knew that although the Western Liao was not a Han dynasty, it was a dynasty deeply influenced by Han culture. Western Liao was the primary and secondary export of Central Plains culture to Central Asia (completed by the Sinicized Khitan people). The official language of Western Liao was Chinese (the administrative language was also Turkic and Persian), the emperor used the Central Plains era name and etiquette, and the official system was a combination of the Central Plains and Central Asia. The ethnic composition of Western Liao itself is complex. There were Khitans, Han Chinese, Turkic peoples, as well as Sogdians, Persians, etc. In response to this situation, the Western Liao continued the north-south bureaucratic system of the Liao State, adopting two different systems in the nomadic areas and the agricultural areas, one country, two systems. After several battles with the Jin army, Yelu Dashi knew that he could not restore his homeland, so he turned to the west and encountered the powerful Seljuk Empire.

Before the westward expedition of Jerodashi, the Seljuk Empire conquered the Qarakhanid in the east and the Ghaznavid in the south, and became the leader of the Islamic world. Sultan Sanjar sent a letter to Yelu Dashi to convert to Islam and was arrogant. As a result, Yelu Dashi defeated the 100,000 army of the Seljuk Empire with 30,000 Liao troops, which once restored the influence of Han culture in Central Asia, and the eastward expansion of Islam for hundreds of years since the Battle of Talas was curbed. Later, Yelu Dashi did not persecute Muslims, but implemented a tolerant and equal religious policy, allowing various religions to develop. After the Western Liao was destroyed by the Mongols, the Central Plains culture in Central Asia was wiped out and gradually completely Islamized until later generations.

Sun Hui understood that if he destroyed the Western Liao now, it was likely to prompt the Islamic forces to advance eastward, not to mention that there was still a strong nomadic people on the eve of the rise of the Mongolian steppe.

Only by keeping these forces at bay and reaching a state of equilibrium, so that neither of them has the strength to go south, will the Song Dynasty in the Central Plains be truly safe.