Luo Zhaoyun took advantage of the victory and started a massacre. This time, he did not seek steady progress, but only wanted to kill the enemy, and gave Tubo a bloody lesson and a psychological shadow.

Chasing for hundreds of miles, slaughtering the backward and wandering Tubo soldiers, pushing them all the way to a pass in Raohe County.

This was the former Sui army stationed in the defense of the Tubo attack. The last time the Tubo army defeated Mai Jicai's team here and seized the place.

At this moment, Luo Zhaoyun chased Tubo all the way back, and the next step was to attack the mountain pass.

"Renovate on site, dig trenches and camp." Some Yuhou and the commanders passed messages to a team of thousands of people.

The Sui army in the northwest was well-trained and chased after the whole day. They were exhausted and began to camp and rest.

This battle was very exciting. Whether it was ordinary cavalry, Modao Formation, or Yan's Armored Cavalry, they all achieved considerable results.

The troops and horses that were catching up to him were just cavalry and were not suitable for siege again. Therefore, Luo Zhaoyun was not in a hurry, but waited for the arrival of the infantry formation tomorrow, using convenient siege equipment, stone catapults, fire urn bombs, etc.

Another point is that the rough black gunpowder has been developed. According to the chemical knowledge that Luo Zhaoyun learned in later generations, he understood that the ingredients of black gunpowder are potassium nitrate, sulfur and charcoal, commonly known as "one sulfur, dinitrogen, and three charcoal". He sent people to find these raw materials many years ago. He had been developing them in Yanyunbao in Zhuo County, but they have not leaked them to the outside world and would not be used too early, and they were stolen by others, so they were prepared.

The manufacturing of black gunpowder is not as complicated as imagined, but the reason why it appeared in the Song Dynasty was because the previous dynasties did not pay attention to this matter, and even no gunpowder craftsmen did a lot of research in this regard.

It’s like Newton saw the apple landing and discovered gravity. However, the ancients knew that the apple landing, but they did not continue to study it in depth.

In the pre-Qin period, some alchemists touched the original prototype of gunpowder. They were just frying the furnace during alchemy, but they were not spread and were valued by dynasties in the era. During the Wei, Jin, Sui and Tang dynasties, fireworks began to appear, which contained some components that constitute gunpowder, but in terms of blasting power and stability, they could not reach the level of black gunpowder. They did not think about continuing to dig and develop for military combat.

As a time traveler, Luo Zhaoyun mastered this theoretical knowledge earlier and sent people to practice it. Finally, he developed it earlier, but the stability still needs to be tested on a large scale.

This time he planned to use it for the Tubo people to shock these barbarians on the plateau, and the news would not spread, killing two birds with one stone.

In the future, he would not use it to deal with Xue Ju, Tang Bi, Liang Shidu and others in opposition to the king. He would keep it secretly and not let it be exposed. He would wait for the decisive battle with Li Tang army outside Daxing City before he could really take it out as a killer weapon.

Because Luo Zhaoyun always regarded Li Tang as his primary enemy, he did not dare to be careless at all. After all, in history, the founding father and son who had the destiny of the country and became a historical fact. He did not know whether he could reverse history. Therefore, he kept black gunpowder, which was his trump card, attacked Daxing City, used black gunpowder, defeated the Tang army, and solved the enemy.

It was already late at night, and Luo Zhaoyun sent his own central army soldiers and personal guards to defend the camp, so that the soldiers of the three armies who fought on the front line for a day would rest and have a safe sleep.

Gar Dongzan knew that the Sui army was exhausted and wanted to counterattack, but his 20,000 troops were even more unbearable. Not only were they tired, but they were also timid. The remaining troops were only three or four thousand, and they sent two teams of thousands to form a suicide squad to attack the Sui army camp at night.

However, Luo Zhaoyun was prepared for a long time, dispersed many scouts and special forces to block and send messages, and the defense army resisted in time, which made the sneak attack fail.

The next day, Xue Wanren and Mai Jicai led their troops to reinforce. They fought against the Tubo Right Army yesterday, and defeated the other side in a bloody battle. They only killed one thousand enemies and suffered 800 damage to themselves, and the vanguard army suffered a lot.

After listening to the report, Luo Zhaoyun nodded slightly. The Tubo soldiers were like Turkic soldiers, with strong individual soldiers and strong combat power. When they encountered clever formations of the Central Plains, advanced weapons, etc., they would be severely damaged. If they had equal forces and fought directly, then the cavalry of the ethnic minority would have a better advantage.

Xue Wanren was used as a 10,000 men to defeat him. He personally led his army to charge into battle, used the sharpness of weapons and crossbow arrows to fight hard, and finally defeated the Tubo cavalry, but the soldiers under his command also suffered many casualties. After comparison, four or six casualties were opened, six Tubo and four Sui army, which had a very good record.

"Waiting for the infantry to arrive and conquer the pass!"

"Young marshal, why not bring a group of men and horses to the dangerous mountains and rivers, and to the road they must pass behind, and to ambush them?" Xue Wanren boldly suggested.

Luo Zhaoyun pondered for a moment and nodded in agreement: "Okay, the number of people cannot be large, it will attract attention. You bring three thousand light cavalry, foot crossbows, etc., and set up an ambush in the dense forest belt of the valley that is the only way to pass."

"The last general understands!" Xue Wanren bowed and immediately counted the troops, leading the people to bypass this mountainous area, insert them into the Tubo border, and intercept them.

Mai Jicai volunteered: "Young Marshal, this heroic pass is lost from the last general. The last general wants to take back himself to avenge the humiliation. Please help the young general."

Luo Zhaoyun glanced at him and said, "Okay, when attacking Chengguan, you will take the lead."

"Thank you, coach!" Mai Jicai smiled and fell here, wanting to regain glory here.

One day later, 15,000 infantry phalanx arrived, installed siege equipment, assembled stone throwing cars, set up cloud ladders, etc., and launched a general attack.

More than ten catapults threw out ceramic fire urns and exploded at the top of the city. Because they were filled with a little black gunpowder, their power became greater. The iron pillars and ceramic pieces flew like pear blossoms, which hurt the faces and bodies of the Tubo soldiers guarding the city. They had too few protective armors, all of which were wild beast leather armor, and there were very few iron armors, so they could not prevent these small explosions.

Puff puff puff!

The guards on the top of the city were constantly injured, screaming and wailing everywhere. Although they would not hurt anyone's lives, they were slightly injured or seriously injured, and they directly lost their combat effectiveness.
Chapter completed!