The aircraft carriers were the shortest of the bunch. They had at most two floors, but this didn't mean that they were small. They were short, but they were wide. What they lacked in height, they made up for with width and surface area.
Their short and wide structure was designed so that they would be able to act as a mobile airfield. Even before the aircraft on them were deployed, their small size didn't diminish how imposing they were.
But as big and imposing as all these mobile fortresses and carriers were, they still looked small compared to the size of the walls. After all, the tallest of them was only 100 meters in height while the walls were a kilometer tall.
The Red and Blue Fire sect had other types of equipment that they used to invade worlds and bring them down, like their floating fortresses, but they couldn't use those here because of the arrangements of the walls.
The walls were fortified with barrier shields that would prevent attacks coming from distances too far from harming the wall. But the barriers couldn't block attacks that originate from close to the ground near the walls.
The weakness of the barrier was intentional. The walls were designed to be vulnerable from close range in order to coax the invaders to attack from close range.
If the walls had been sealed tight, then the priority of the invaders would be to destroy the barrier with any means necessary. But since that isn't the case, the invaders ignored the barrier and chose to attack from an easier avenue.
This arrangement prevented the Red and Blue Fire sect from bringing out everything they had and throwing it at the walls. But even what they were forced to use was enough to intimidate the invaders.
To be fair, not everyone was intimidated. In fact, most of the defenders were bewildered and confused by the assortment of weapons and machines of war that the Red and Blue Fire sect had brought forth for war.
The defenders were confused because they had never seen structures like this before. In past wars, the main combatants have always been individual forces.
It can be said that the main unit of war that they were used to was infantry. But saying that might be considered an exaggeration because it might lead to the misunderstanding that cultivators fought together as an army.
It is very difficult to make cultivators fight together because they have different capabilities in terms of techniques and spells. And sometimes, a single person might be strong enough to overwhelm any amount of cooperation.
On the other hand, the Red and Blue fire sect has mastered the use of large weapons of war. This is how they managed to invade and defeat entire worlds, even when they lacked the advantage of numbers and were vastly outnumbered.
In summary, the level of technology utilization for the war on both sides was very different. This created the situation where the defenders were confused and intimidated by the new, strange machines.
Only a few people like Arthur had the presence of mind to be fascinated by the assortment of war machines. He even began taking note and explaining the things he observed about the war machines to the formation breaker.
However, the defenders were only confused, not helpless against the machines of war. Once the mobile fortresses and carriers got past the barrier and could now attack the walls without the barrier interfering, they automatically came within attack range of the walls.
The defenders didn't have fancy machines and equipment. All they had were formations, and it would have to be good enough if they were to win this war.
Some of the formations that had been inscribed onto the walls were attacking formations. And there were attacking formations of various kinds.
There were formations that blew large columns of fire at the enemy like flame throwers. This particular type of attacking formation was capable of turning the area in front of a wall into a sea of fire.
There were also attacking formations that produced earth spikes from the ground, launched ice spears, cut everything in front of them with wind blades, and launched water jets at enemies.
All of these attacking formations were activated as soon as the invaders got within attack range. But the mobile fortresses stood their ground and remained unharmed thanks to the barrier shields that they were equipped with.
Not only were the mobile fortresses fine, but they were in the perfect state to retaliate. With a single order, they began unloading all the ammunition in their possession in the direction of the walls.
The roar of gunfire shook the world. The impact of all the shells and bullets on the wall also shook it.
The first wall withstood the first barrage without falling, but it was damaged. Some of its attacking formations were also damaged and stopped functioning.
The mobile fortresses stopped at a distance from the walls and were content with just throwing ammunition at the walls from their comfortable position. They didn't want to navigate the most traps on the way to the walls at all.
This forced the defenders to come up with a solution. After all, they couldn't just allow the invaders to shoot them all they want.
The invaders were still enduring the barrage of elemental attacks from the attacking formations attached to the walls, but this was not enough to pressure them. If things continued like this, the walls would be taken down one by one with only minimal damage to the invaders.
In order to prevent this outcome, some of the defenders were sent to attack the mobile fortresses. Their goal was to sabotage the fortresses and destroy them if possible.
These people were not sent across the surface of the battlefield since it wasn't currently safe and was saturated with firepower from both sides. They were sent through the underground passages that had been dug into the ground before the battle.