Kayn followed the scouts he saw flying over the fortress. He intentionally left some distance between himself and it turned out to be the correct decision.
"Damn, they really brought out a whole fortress worth of army for this…"
If the fortress before contained dozens of demons, the current army he saw in the distance numbered around one hundred demons.
A number that he would definitely have a hard time fighting, if he didn't have any preparations beforehand.
And he needed to make sure that his preparations didn't come to waste.
With that in mind, Kayn approached the army closer and recognized another elemental demon leading the army.
The demon had also recognized him as they locked eyes with each other.
'Yellow-skinned demon, something that I've never seen before. I wonder what kind of elemental demon he is…'
Seeing the army on the ground, some still oblivious to his presence, Kayn tilted his head and smiled.
'Well, why don't I just find out?'
Kayn opened up his four hands and cast 4 spells simultaneously.
"Ice Bullet."
The second the runes formed in front of Kayn's hand, the wind demon shouted, amplifying his voice with wind magic,
"DEFEND YOURSELVES!"
The wind demon quickly cast a wind barrier, manifesting in the form of a wind wall that protected his front and was wide enough to protect the demons standing beside him.
But Kayn had already thought of the elemental demon's possible ability and only invested a single spell in his direction.
His other three spells were aimed at the other demons.
'As expected from an elemental demon, a wind one, they're as strong and annoying as other elemental demons.' Kayn thought when he saw the wind wall had diverted his ice bullets, sending them up towards the sky.
But his other three spells hit their targets.
The ordinary demons were using all kinds of methods to save themselves.
Some began using their strong physique to dodge and run away, and others who were proficient in magic brought up barriers of their own to defend against the ice bullets.
But an ordinary barrier without any affinity was weaker compared to a barrier with an elemental affinity.
The barrier could stop more than half of the bullets, but the remaining bullets passed through and hit the ordinary demons who were confident in their magic.
The one who trusted their bodies and ran away had a higher rate of survival compared to the ones who relied on their magic.
With Kayn being a distance away from them, the faster and stronger demon had enough time to get out of the way.
But Kayn wasn't done.
To make it fairer for the magically proficient demons, Kayn raised walls of ice all around the army, impeding their movements and making it harder for those demons to simply run away anywhere they liked.
He also built four thick and long ice walls, trapping a lot of the army inside the square of ice.
Seeing this, the wind demon didn't just stay still.
"Winged demons, with me!"
The wind demon spread out his wings and flew up, flying much faster than Kayn was able to do.
The other demons with wings on their backs also followed after him, all flying towards Kayn behind the wind demon.
"Oh! You care about the lives of your minions! What a surprise!" Kayn shouted, seeing the wind demon flying at him with a speed that surprised him.
'That's a wind demon for sure. I won't be able to just run away from him using my wings.'
"Frozen wind."
Kayn sent out the spell towards the speeding wind demon. No matter how fast the wind demon could fly using his magic, he wouldn't even be able to move if his whole body were frozen.
But before the frozen wind could even get near him, the wind demon already felt the insidious cold wind, and cast a spell to counter it.
"Blowing wind."
A wave of wind, one that overpowered the frozen wind, crashed against it, sending the frozen wind back to where it came from.
Kayn felt the frozen wind come back to him. But because it was a spell that sent out raw ice mana from himself, when the ice mana tried invading his body, it realized that it was a part of the body it was trying to invade.
So the frozen wind did nothing other than return the mana that Kayn had used to cast the spell.
"Tch. You're gonna be even more annoying than an earth demon, are you…."
Knowing that sending another frozen wind wouldn't result in anything different, Kayn flew away.
His hands returned to casting ice bullets at the army of demons below him.
Now, with the ice walls around, more and more demons were hit by his ice bullets.
It looked like Kayn was about to slowly dwindle away the army before it even arrived at the fortress.
Thinking that it might be Kayn's strategy, the wind demon flew even faster.
"I won't let you!" The wind demon shouted as it cast more spells.
"Wind Blade!"
Kayn turned his head towards the wind demon, his eyes frowning as he saw the spell manifest in the world.
He couldn't see anything, but his mana sense told him a bundle of mana was flying in his way.
Kayn quickly stopped casting ice bullets with his two hands and cast another spell.
"Ice Claws."
Kayn then slashed his ice-coated claws towards the bundle of mana the second it arrived in front of him.
The bundle of mana soon dispersed, and there wasn't any damage to his ice claws except for one long superficial cut on his ice claws.
Looking at the cut, Kayn thought, 'It wasn't anything too powerful, but it would definitely leave a nasty cut if it had hit bare flesh instead.
Moreover… The damn spell was invisible…'
Realizing how dangerous it was for him if he were to force more, Kayn then decided to end his farce.
The wind demon had long arrived in front of Kayn, but he didn't fly any closer.
Even though the wind demon had met an ice demon before, he didn't know what kind of abilities this particular ice demon had.
He was familiar with the frozen wind from before, as the previous ice demon also used it, but the small ice projectiles that the ice demon sent out earlier were something that the wind demon had never seen before.
The wind demon decided that he would need to take down the dangerous ice demon right here, in the sky, where he held an advantageous position.
"Delay: Ice Bullet Explosion."
The ice demon suddenly cast another spell, 4 of them actually, each with one of his hands, and the wind demon prepared to summon another wind barrier or just simply dodge, depending on the spell that would soon manifest.
But he was surprised to see that nothing appeared in front of him, and he could also not sense any mana from around him or the ice demon.
Seeing his confusion, the ice demon opened up his mouth,
"I believe you put a little care into your subordinates. I know it's most likely not related to camaraderie or anything like that, but I believe that for whatever reason, you don't want them dying needlessly."
The ice demon then pointed his finger towards the army on the ground.
Between the army that was stuck in the ice walls, four spots were glowing with light as the wind demon felt mana continuously gathering on those four points.
Before the wind demon could ask for an explanation, the ice demon spoke on more,
"It's a new spell that I've come up with, or at least a failed version of something that I tried to create.
But they have their own perks despite being a failed experiment!
You see, the spell I have cast will gather mana from the surroundings, as it is currently doing now, then in under half a minute, it will manifest the spell using all that gathered mana.
The resulting spell would be stronger than if I tried to cast it manually, so just imagine how many of your minions I can take down using that spell?
If you don't want that to happen, you'd better help them deal with the ice walls! "
After saying the last sentence, the ice demon turned his body and flew back in the direction of the fortress.
The wind demon was tempted to chase after the ice demon and force him to fight in the air, but decided in the end that it was too much of a risk.
Gritting his teeth in annoyance and anger, the wind demon just left the demon ice alone and returned to his army, casting wind blades over and over again to help his army break through the ice walls.