With sufficient supplies, Su Zhizhen prepared to continue the attack, and the troops were directed towards Boston City, the capital of the Boston Empire. But in front of him was the Wudalianhu area, led by Lake Michigan, where Marshal Pershing led a rereplenished army of two million, supported by Boston's Wudalianhu Fleet, which had more than 30 river gunboats.

Su Zhizhen also had a headache for the barrier of the lake area, not because the lake area was too big and completely blocked the way forward, but because he had to settle down here, and chose to continue to move forward after completely controlling the Wudalian Lake area.

The lake area covers an extremely large area, and the lake shore is long, spanning the seven northern states of the Boston Empire, if the Chinese army bypasses the lake area and continues to advance, the Boston army relying on the lake area can fight a water guerrilla war. They can use numerous ships carrying infantry to land randomly on the shores of various lakes and attack the logistics and supply units of the Chinese army before withdrawing from the water, or they can use river gunboats carrying cannons to attack the supply convoys of the Chinese army in the coastal areas, for which the Chinese army has no choice, and once the forward attack fails, Su Zhizhen's troops may be encircled.

Faced with this unfavorable situation, Su Zhizhen first launched an attack on Green Bay City, which is close to the Lake District. The city of Greenbay is not large, with a population of just over 20,000 people, but the city is located on the western shore of Wudalianhu, right in the way of the Chinese army's advance, and most importantly, there is a small shipyard on the edge of the city near the lakeshore.

If you want to fight the Bostonians on the lake, you must have your own fleet, so that you can gradually control the lake and turn disadvantages into advantages.

This time, the 10th Army led by Wang Xiucheng became the vanguard, and they quickly surrounded this small city. Seeing the appearance of the Chinese army, the Boston army quickly launched a counterattack, and a large number of rockets crossed a distance of 20 kilometers and covered the advancing Chinese army, which was the first time that the Boston Empire's 300 mm 18-barrel rocket artillery entered actual combat.

The vanguard regiment, which was caught off guard, suffered heavy losses, more than ten chariots were destroyed, more than four hundred people were killed, and they were forced to retreat. Seeing this situation, Wang Xiucheng put away his contempt, he quickly ordered the heavy artillery unit to carry out a large-scale artillery attack on the city, but soon the Boston people's 360 mm heavy artillery launched a counterattack, fortunately, the artillery positions of the 10th Army were very scattered, so the casualties were not large, only one artillery company of three 240 mm self-propelled howitzers and a cannon radar vehicle was destroyed, dozens of casualties only, but Wang Xiucheng also found that the attack was difficult to carry out by the army alone.

More than 100 albatross dive bombers launched precision bombing of the city, many fortifications were destroyed by high-explosive aerial bombs, and the Boston army in the city also launched a stubborn resistance, using anti-aircraft guns of various calibers to carry out counterattacks.

After all, the propeller planes were already too slow, but the Boston Army was equipped with quite a few 88-millimeter or even 100-millimeter-caliber anti-aircraft guns, and in the face of a large number of anti-aircraft guns, more than 20 planes were shot down, but they successfully destroyed four 360-millimeter heavy artillery positions in the city.

The size of this large-caliber heavy gun was too large to hide it completely, so bombers could easily find and destroy them. After eliminating the enemy's large-caliber heavy artillery, the Tenth Army began to bombard with 240-mm howitzers, while the 300-mm rocket artillery of the Bostons was too close to reach the other side.

The shelling lasted for two days, and with a large number of shells from the Chicago Industrial District, the Chinese army did not spare ammunition, and they almost completely destroyed the city of Green Bay with a dense number of shells, and the 300-millimeter rocket launchers and the few Rat fighting vehicles suffered heavy damage because they could not hide. The 10th Army soon launched an offensive, relying on Grizzly 3 tanks and a large number of White Bear 2 troop carriers, and more than a division of troops quickly entered the city.

The Bostonians, who had been shelled for two days, suffered heavy losses and were unable to organize effective resistance, they were quickly wiped out, and the small shipyard near the lake fell into the hands of the Chinese army. Although the battle went quite smoothly, the successive appearance of high-powered weapons on the other side made the Chinese army show its inferiority, and the Bostonians gave full play to the advantages of internal warfare, specializing in making those difficult to move but powerful weapons to fight against the powerful Chinese army.

After receiving this news, the country quickly sent some of the new weapon drawings to the Chicago Industrial Area, and a batch of new weapons was quickly put into mass production and delivered to the troops. The new Grizzly 4 is a transitional weapon, which was also created specifically to deal with the Rat vehicle.

The new Grizzly 4 has lackluster internal electronics, basically copying the configuration of the Type 3, but with a much larger hull. A five-hundred-and-twenty-horsepower diesel engine is installed in the seven-meter-long body, which gives the vehicle great power and allows it to reach speeds of up to 40 kilometers per hour.

A 122 mm tank gun on the high turret, there is a special smoke exhaust device in the middle of the gun body, and a 12.7 mm parallel machine gun and an anti-aircraft machine gun of the same caliber are installed on the hull, providing close combat and necessary air defense support for the combat vehicle, and the 160 mm composite armor plate on the front of the hull uses a five-layer composite mode of three layers of steel armor, one layer of ceramic armor, and one layer of foamed flexible armor, which ensures the defense of the combat vehicle at the same time, but also greatly reduces the weight, and the total weight of this combat vehicle is only more than 60 tons, almost a third of the Boston Army Rat Chariot.

In addition to the Grizzly 5 tank, the Monty Python 1 train gun was also copied, although the caliber of this powerful train gun is only 280 mm, which is one level worse than the 360 mm heavy gun of the Boston people, but due to the higher metallurgical level of the Chinese Empire, the artillery has a higher diameter, and it can completely suppress the Boston people in terms of range, and because of the small caliber and the light weight of the shells, its rate of fire is far from that of the Boston heavy artillery.

These were preparations on the part of the Army, and after the capture of Green Bay, the shipyard began to be renovated, with all kinds of equipment brought from the Chicago Industrial Area, the shipyard was soon enlarged, and the new three-thousand-ton dockyards were built at once, five of which were to be used to make new river gunboats.

Since the lake was wider than the river, and there were not many sharp bends, there was no need to build the kind of 53-ton Great Salt Lake-class gunboats suitable for the river, so the Bostonians built 410-ton Lake Mead-class gunboats in the Wudalian Lake. On the open lake, it is suitable for the activities of gunboats of large displacement, and the 1005-mm main guns equipped with them have stronger firepower and can give full play to their advantages in firepower.

In the face of more than 30 Lake Mead-class river gunboats from the Boston people, the Chinese Empire was not to be outdone, and they directly launched the Baishan-class river gunboats. The Baishan class was once used to name the first type of maritime gunboat in the Chinese Territory, but that class of ships was unsuccessful, and the main guns were quickly removed and replaced with anti-smuggling patrol ships.

The reactivation of the name this time can be regarded as a kind of nostalgia for the Baishan-class gunboats. The new Baishan-class river gunboats have a displacement of up to 485 tons, and in order to speed up production, the warship did not redesign the main gun, but directly used the 122 mm turret of the Grizzly 5 tank, which could greatly speed up production. Each gunboat was equipped with two turrets, in addition to four 40-mm high-level dual-purpose guns and two 12.7-mm machine guns.

Due to the small size of the warship and the use of a large number of ready-made technologies in the weapon system, the construction speed of the Baishan-class river gunboats was very fast, and in just half a month's work, the first batch of five Baishan-class ships quickly slid off the slipway and began to outfit, and the new hull began to be built again.

The rapid construction of river gunboats by the Chinese army in Greenbay City was obviously to compete with the Boston Inland Lake Fleet for control, which made the Bostonians very anxious. Unable to wait for the opponent's fleet to grow, the Boston people decided to take advantage of the fact that the Chinese army's gunboats were not yet completed, and sent a small fleet of thirteen gunboats, and they planned to destroy the Chinese army's shipyard first, so as to stop the rapid growth of the opponent's Neihu fleet.

Lieutenant Colonel Douro led his thirteen gunboats to set off at night, and under the cover of the reeds on the lake, they quickly rushed towards the shipyard in Greenbay City. Although the Chinese army does not have any armed forces on the lake, this does not mean that they do not have early warning facilities.

After the Chinese army occupied the shipyard in Greenbay City, they began to install underwater speakers within a five-kilometer radius of the shipyard. These underwater speakers are actually relatively rudimentary sonar systems, the cost of the loudspeakers is much cheaper than the sonar used on warships, it can convert the sound in the water into electrical signals, through the wires connected to them back to the shore, although they do not have a positioning function, but as an early warning is still very useful.

When Lieutenant Colonel Douro's fleet passed through the underwater loudspeaker locations, the sound of propeller paddling and diesel engine tremors was quickly captured, and the listening post on the shore immediately picked up the situation, and all the garrisons on the shore became nervous. At a military airfield outside Greenbay, eight modified albatross dive bombers quickly took off and headed for Lake Michigan.

The eight dive bombers, specially adapted for night operations, were equipped with not only navigation radar, but also infrared night vision sights, although their bomb load was reduced by a third due to the addition of these electronic equipment, but it was all worth it. As a dive bomber on night duty, when eight albatross flew over the shipyard, they quickly spotted the incoming enemy ship.