The guns were powerful. Unfortunately, they were small and couldn't cause too much damage if they didn't hit a critical part of the body.
It was especially important that they hit a critical part of the peak gem kings because the guns being able to output 100C only meant that they could injure the gem kings if they struck them. It didn't mean that the guns could kill them instantly with a single hit.
And as fate would have it, the gem kings only have one critical point in their bodies. This critical point is their heart core, and it is buried deep within their bodies.
As long as their heart core is intact, they will be able to survive even if their whole body is shattered. Because of this, any injury that doesn't affect their heart core cannot be lethal. This was why it was so difficult to kill the gem kings despite ambushing them with the guns.
Ten guns had to focus on one gem king at a time and make sure to smash them into ashes in order to kill them. This allowed the other four peak-level gem kings to retreat to safety.
Then the bay door of the mothership was opened, and the plant puppets were sent out to fight the gem people. The golem puppets were not sent out with them this time around because the strong magnetic field of Aurora had made their energy cores unstable.
The fact that their bodies were made out of metal only made the environment more unsuitable for the golem puppets to appear. So only the plant puppets that could remain stable could be used to repel the enemies.
However, the puppets were at most at the peak of the fourth mortal coil. This puts their strength at 10C. This was nowhere enough to defeat all of their enemies. So the top fighters of the main army still needed to come out to fight.
The two-star right and left division commanders of the army didn't come out to join the fight because their strength was around 10C. They couldn't add much to the situation and were needed to lead the basic units of the army, so they were asked to remain within the mothership on standby.
Only the three-star battalion commanders and above were allowed to leave the mothership and join the fight. This was because the three-star battalion commanders possessed armaments and could produce power that was reliably at 20C.
Above the three-star battalion commanders were the four-star regiment commanders. There were three regiment commanders, and they were all at the nascent soul level.
Finally, there was Arthur. As the leader of the army, he had to come out and show that he was capable of leading the army to victory now. If the environment is determined to be too much for him to handle and he can't perform well, then the patriarchs might decide to give up on the invasion and return to Ethera immediately.
Arthur and the three battalion commanders each picked one of the peak-level gem kings to fight. Unfortunately for them, their enemies didn't fight them one-on-one. Each peak gem king fought them together with their subordinates.
In response to this unfavorable situation, Arthur decided not to fight with his body and instead chose to use spells. This was because spells could be used to attack more than one person at a time, compared to fighting with fists.
Because they were high in the sky, he decided to use lightning spells, not wood spells, to fight. And as usual, he started with some lightning bolts and the Lightning Net spell.
The Lightning Net spell creates a flat layer of lightning around him that turns his immediate surroundings into a lightning mine field. He can create many layers of lightning and place them on top of one another, all centered around him, if he wants to increase the lethality of the spell.
A big weakness of the Lightning Net spell is that an enemy can avoid the layer of lightning net by attacking him from above. He can rectify this weakness by constantly moving the position of the layer of lightning around him in a sweeping motion. This option would require more mental control for it to work.
He can also create many layers of lightning around his body to block every direction of attack. This option would require more energy and more control, though. But thanks to the strong magnetic field, he didn't need to do all that work to make the Lightning Net more troublesome to deal with.
The strong magnetic field from Aurora interacted positively with the magnetic field of his golden core and made the single layer of lightning spread out and become a spherical ball of lightning around him.
This consumed more energy from him, but he didn't need more mental focus to control the behavior of the spell. In fact, he realized that he was expending less mental focus to control the sphere of lightning than he usually did to control a single layer of lightning.
This was because the strong magnetic field of Aurora was enhancing the control of his lightning energy by making the energy that left his body behave like energy that is still inside his body. In other words, the strong magnetic field in his surroundings made him control the lightning as if he were controlling his internal energy.
Since controlling one's internal energy is always easier than controlling external energy, it became very easy for him to wield the Lightning Net spell. But this was just the tip of the iceberg of the advantage that the strong magnetic field had given him.
After he struck someone with a lightning bolt, he realized that he could control how much damage the lightning bolt would do and how much of the lightning bolt would be expended in the attack. This way, he could preserve some of the power of the lightning bolt and not make it explode all at once.