After the fall of Suizhou, all the 58th Army was killed except for the 3rd Regiment of the 527th Division that escaped from the city. Therefore, the Beihai defenders in the area from Suizhou to the Crescent River Valley were fiercely attacked by the Shangdang Army before they learned the news of the loss of Suizhou. In this attack on Beihai, the Shangdang Army was pouring out, with a total strength of 2.4 million. Excluding the 500,000 cavalry who were burning and killing in Suizhou City, there were still 300,000 cavalry in Subutai's hands. In order to annihilate the Beihai armies stationed in the three passes and eleven cities as much as possible, the Subutai troops were divided into 14 routes, and the 300,000 cavalry were divided into six routes to attack the six cities that were closer to the Crescent River Valley. The rest of the infantry was roughly divided into eight routes, attacking three passes and five cities that were relatively close. In addition, Subutai secretly sent an elite army to ambush in the dense forest fifty miles east of Jianzhu Peak, preparing to block the Beihai army fleeing eastward.

In fact, Bai Hui, the deputy commander of the Menglan Legion, who was ordered to garrison the Crescent River Valley, had the most elite 200,000 troops of the Menglan Legion in his hands. If you attack at this time, you will definitely achieve a great victory if you attack any of the 14 routes of the army. However, the lack of news was destined to make the Menglan Army miss the only chance to reverse the defeat.

Before the start of the war, the Menglan Legion underwent a major expansion, and the total strength was increased to 700,000 (excluding local garrisons). As early as half a year ago, Shiraishi had determined the battle plan with the Crescent River Valley as the fulcrum of defense. Taking advantage of the swamps in the Crescent River Valley area and the location of the Crescent River flowing through it, Baishi organized the Beihai people to plow the road for fields, so that Chengtian's cavalry could not cross the Crescent River Valley at all, and could only choose to force the Crescent River to cross. And if you want to force the Crescent River, you must occupy the Tsim Sha Pass in the upper reaches of the Crescent River. Otherwise, forcibly crossing the river would be treated as a live fish by the North Sea Army. If you want to capture Tsim Sha Pass, you must take Feiyu Pass, the core defensive position of the Crescent River Valley on the west bank of Tsim Sha Pass, and break the position that the two passes are horns of each other. Therefore, the entire Menglan Legion deployed 200,000 main forces in the Crescent River Valley area, which was personally led by Bai Hui, the deputy commander of the legion. In addition, 100,000 troops were stationed in Tongtian City, and 200,000 troops were stationed outside Menglan City, as the reserve of the Menglan Legion, which was personally controlled by Bai Shi. So, west of the Crescent Valley, there were only 200,000 regular troops in the North Sea.

And these 200,000 troops, except for the Seventh Army, are not the main force of the Menglan Army. To put it bluntly, Baishi knew that the Chengtian army was strong, and he was unwilling to let the main force be consumed on the border line too early and needlessly, which led to Suizhou being broken by the Chengtian army in only half a day.

In addition to the 58th Army stationed in Suizhou, a total of 17 divisions were stationed in Sanguan and 11 cities, plus local garrisons in various places, with a total strength of about 250,000. Among them, the 99th Army and the 60th Army were responsible for defending the six cities closer to the Crescent River Valley. The 89th and 87th Armies were responsible for defending five other cities near the direction of Suizhou. As for the three passes of Kanmen Pass, Xianggongling and Jianzhufeng in the core area, they were guarded by the 101st Division, the 47th Division and the 7th Army respectively.

Among these troops, only the Seventh Army was the main force that existed before the expansion, and its commander Sun Yaoguang was an ice general, nicknamed "Thunder Light", and enjoyed a good reputation in the entire Beihai army. The Jianzhu Peak, guarded by the Seventh Army, is an important transportation hub connecting the three passes and eleven cities. Once Jianzhu Peak falls into the hands of the enemy, the 89th Army and the 87th Army will be cut off from retreat, and there will be no place to bury. Even though Shiraishi was reluctant to place heavy troops west of the Crescent River Valley, he did not want his troops to die in vain. Therefore, after much hesitation, Shiraishi sent the Seventh Army, which was very strong in combat effectiveness, to sit in Jianzhu Peak, and let the "Thunder Light" command all the troops in this area. Before the battle, Shiraishi had secretly told Sun Yaoguang that if he could not defend it, he would safely withdraw the army to the Crescent River Valley.

Therefore, in Subutai's plan, there is one point that he did not talk to Cha and Buhua. That is, for the Jianzhu Peak, where the Seventh Army is located, Subutai will only make a feint and will never make real efforts. Considering the strength of the Seventh Army and Sun Yaoguang's prestige, except for Chahe Buhua, the rest of the Shangdang Legion is only afraid that they are not the opponents of this "Thunder Light". Therefore, Subutai decided to force the Seventh Army to take the initiative to withdraw from Jianzhu Peak, and let the corps commander Cha and Buhua personally block this "thunder light".

On the morning of April 27, 1215, the 87th and 89th armies of the Menglan Legion were suddenly attacked by more than one million Chengtian troops. Immediately afterwards, Kanmen Pass, Xianggongling was also attacked by a large-scale attack by the Chengtian army, and the sound of killing shook the sky.

Jianzhu Peak was no exception, and one of the 100,000 leaders of the Shangdang Legion led his 100,000 men to attack the Jianzhu Peak Fortress. It's just that after a fierce attack, this unit that was originally a "feint" was defeated. The Seventh Army guarding Jianzhu Peak, under the leadership of the army commander and the ice general "Thunder Light" Sun Yaoguang, first withstood the fierce attack of the enemy army with the danger of Jianzhu Peak, and then launched a counter-charge against the 100,000 enemy troops in front of it, and finally defeated the enemy in the front. Among them, Sun Yaoguang took the lead, and with a thunderous momentum, he shot away the leading Baitu Chang and led the Seventh Army to behead 50,000. Subsequently, Sun Yaoguang took the initiative to attack and once again took advantage of the victory to defeat the Chengtian army besieging Xianggongling.

"Report to Lord Bing General, my 47th Division suffered more than 5,000 casualties, more than half of the losses. If it weren't for the timely reinforcements of the Ice General, Xianggongling would probably have been lost. In front of Sun Yaoguang, Qian Zheng, the 47th Division's ice soldier, said with a disgraced face.

"The situation would have been known. Qian Bingshi, how many enemy troops are besieging Xianggongling today? Just now, General Ben just drove them away and did not observe them too closely. Sun Yaoguang said.

"It's hard to say. However, judging from the military flags, there were no less than 200 maps of the Chengtian troops attacking our Xianggong Ridge, and this is what I can see from the picture flags waved by the enemy when attacking, at least more than 200 figures. Qian Zheng thought about it and said affirmatively.

"That's weird. The Chengtian army is based on a thousand people, and it is clear that my Jianzhu Peak is a key fortress connecting Suizhou to the Crescent River Valley, but the Shangdang Army only sent a hundred map commanders to attack. And in the process of relieving the siege for your troops just now, Ben General personally killed two hundred commanders of the Chengtian army. What is the purpose of such an abnormal way of using troops?" Sun Yaoguang said with some doubts.

Since the enemy dares to attack Kanmen Pass and Xianggongling on a large scale, doesn't it mean that Suizhou City, which was defended by the 58th Army, has been lost?" Qian Zheng, an ice soldier of the 47th Division, suddenly thought of a very serious matter.

When Sun Yaoguang heard this, he thought for a little and showed an expression of disbelief. The "Thunder Light", which had been fighting for a day, suddenly realized at this moment that Suizhou was only afraid that it would be broken by the Chengtian army. Otherwise, he would not have been attacked so violently.