Light weapons like firearms are very ineffective when facing fortifications.
Relying solely on the special police team to attack and capture the fortified mine stronghold would be an absolute pipe dream.
After the special police team withdrew, the Imperial Army, stationed in the rear, immediately launched a full-scale assault on the mine.
The Imperial Army's Guard Brigade was the core ace force of Kaiyaton.
This army was equipped with extremely advanced weaponry and possessed a large number of heavy weapons.
Their combat effectiveness was far superior to that of a ragtag unit like the 75th Brigade!
Once the Guard Brigade launched its offensive, it took only a day to breach the outer defense line of the mine.
With the outer defenses lost, Liu Kai Xuan immediately led his personnel to retreat into Wangyun Mountain for refuge.
Wangyun Mountain had steep terrain, making it easy to defend and difficult to attack!
Before the war began, Liu Kai Xuan had already constructed several strongholds in the mountains and stored some provisions within them.
Now that all personnel had retreated into the mountain strongholds, their safety was temporarily secured.
The Imperial Army had dispatched some units to launch a strong attack into Wangyun Mountain.
However, the troops that entered the mountain were ambushed, suffered some losses, and were forced to retreat.
Tang Ke, the commander of the Guard Brigade, believed that his troops had completely occupied the Kai Xuan Oil Field.
He felt that the mission assigned by His Majesty the King had essentially been completed, and there was no need to engage in difficult mountain warfare, which would only lead to increased casualties.
Tang Ke reported his intentions to Kaiyaton and received his support.
After all, the Guard Brigade was one of Kaiyaton's few ace forces.
Kaiyaton had invested a massive amount of capital in training the Guard Brigade.
During this attack on the mine, over a hundred soldiers were lost, and many heavy weapons were destroyed.
Every time Kaiyaton thought of these losses, he felt immense pain.
That night, within the mountain stronghold, Liu Kai Xuan launched a counterattack against the Imperial Army's Guard Brigade using drones.
Simultaneously, before the counterattack began, Liu Kai Xuan had already dispatched the Luo Mu and Lei Mu squad to infiltrate the royal city and launch an assault!
Liu Kai Xuan's primary method of counterattack was not head-on confrontation but the clever utilization of his drones.
By using drones to drop bombs and launch small missiles, he could engage the enemy beyond visual range.
This allowed him to eliminate enemies while minimizing his own casualties.
For Liu Kai Xuan to defeat the Imperial Army's Guard Brigade through superior strategy with fewer forces, he had to strictly control his losses.
After several days of high-intensity combat, Liu Kai Xuan's guards also suffered severe losses.
Some guards died in the crossfire, while many others chose to withdraw under the immense pressure from the Imperial Army.
The guards were, fundamentally, a "job."
Liu Kai Xuan approved all personnel who "resigned" and withdrew.
As for those who fled without notice, they were all treated as traitors.
After all the commotion and turmoil, only a little over a hundred guards remained by Liu Kai Xuan's side.
Fortunately, Liu Kai Xuan did not expect these individuals to accomplish major tasks.
The real combat power was concentrated in the elite robot combat squads.
Otherwise, Liu Kai Xuan would have likely been defeated long ago.
Late at night, Kaiyaton lay in bed, sound asleep.
"Boom!"
Suddenly, a deafening explosion erupted, causing the entire palace to shake violently.
"Rumble..."
Then, several more thunderous booms echoed.
"Ah..." Tie Ma Sha, terrified by the loud explosions, covered her head with her hands and cried uncontrollably.
At the same time, a large number of imperial guards burst into the room.
Several soldiers, working together, grabbed Kaiyaton's arms and forcibly dragged him and Tie Ma Sha out of the bedroom.
Tie Ma Sha roared, "Let go of me, you fools! Are you rebelling?"
The soldiers remained unmoved, dragging Kaiyaton and Tie Ma Sha towards the nearest underground bunker.
Soon, a soldier rushed in to report the situation.
"Report to Your Majesty, the main hall of the palace has been attacked by unidentified armed personnel, and the main structure is severely damaged!"
"Report to Your Majesty, the Anju Hall of the palace suffered a devastating blow, and its main structure was leveled!"
"Additionally, side halls and multiple residences were attacked, resulting in heavy casualties!"
"Quickly investigate who this audacious madman is who dares to assassinate me!" Kaiyaton roared fiercely. "Find these audacious fanatics and annihilate them completely!"
A general reporting the situation said softly, "Your Majesty, I suspect this was the work of Liu Kai Xuan!"
"In the past year or so, only Liu Kai Xuan has had severe conflicts with Your Majesty!"
"Moreover, the conflict has not yet completely ended!"
"It's that beast Liu Kai Xuan indeed!" Kaiyaton spat through gritted teeth. "Quickly connect me with General Tang Ke. I will utterly destroy Liu Kai Xuan!"
"Yes, Your Majesty!"
Soon, Kaiyaton connected with Tang Ke.
On the phone, Kaiyaton ordered Tang Ke to spare no expense in completely eliminating the remaining forces of Liu Kai Xuan.
Tang Ke assured Kaiyaton that he would increase the intensity of the attacks and would absolutely not allow Liu Kai Xuan's forces to cause further trouble.
Complete annihilation, while easy to say, was extremely difficult to execute.
Wangyun Mountain was steep and its terrain was fragmented and broken.
The steep slopes were covered with a large amount of rubble and gravel.
Walking on the mountainside, one could easily tumble down a cliff with a single misstep.
Even tanks and armored vehicles found it extremely difficult to climb the slopes.
Furthermore, steep ravines cut across most of the mountainous terrain.
Such an area was not at all suitable for a full-scale offensive by large mechanized armies.
If Tang Ke were to send the armored brigade to encircle and annihilate Liu Kai Xuan's remaining forces, they would have to abandon their heavy weapons and advance into the mountains lightly armed.
However, if the Guard Brigade discarded their heavy weapons and fought only with light equipment, how much combat effectiveness would they retain?
Even Tang Ke himself was unsure about this.
To reduce casualties and complete the mission quickly, Tang Ke requested the special police team to accompany the Guard Brigade on an expedition into the mountains to pursue Liu Kai Xuan's remaining forces.
First, they would conduct a systematic search to locate the hiding places of Liu Kai Xuan's remaining troops.
Then, they would list the precise coordinates of the target locations and transmit them to the heavy artillery units in the rear.
In this manner, a single, intense artillery barrage would be sufficient to annihilate the majority of the rebel forces.
After inflicting massive casualties on the rebels using this method, the main forces would then be dispatched into the mountains to hunt down the remaining stragglers.