The clusters of red lightning moved at breakneck speeds before crashing onto the plant monsters with all they had. The monsters were subjected to such an impact that it looked like they had been pushed back in unison by a wave of red lightning.
Eren was still not able to completely control his mana circuits the way Alephee wanted him to. Thus, he still had some limitations in controlling the summoned creatures using Alephee's trick.
As a result, the red lightning bulls couldn't be retained for longer after Blitz Steps was integrated into them. They could only be employed for launching kamikaze attacks.
However, the red lightning bulls' limitations didn't matter much to Eren. Compared to Rey's woodland creatures, they were very light on his mana consumption. Plus, their attacks delivered exceptional destruction powers.
The red lightning bulls pushed Old Rey's woodland creatures farther back. The detonation of the red lightning clouds that followed completely obliterated their bodies. Unlike fire-based attacks, they couldn't offer much resistance to red lightning's destructive nature.
Old Rey watched the scene unfolding around him with horror. He looked at Eren who was flying in the air at a distance from him with genuine fear.
'Summoned creatures that can use movement spells along with their inherent spells. Flying snakes can breathe fire and drop fireballs. And a murder-seeking maniac who can shift between two classes like it's no big deal.
What… What kind of summoning is this? And I have seen a fair share of fucking everything there is to see damn it.'
Old Rey pondered in his head with a look of dismay on his face. He decided to try to salvage the situation.
"Young man, I think we were off to a rough start. Why don't we…"
? Eren shook his head in denial when Rey started speaking with forced politeness in his tone. Before old Rey could say something more, he observed that a relatively massive red bull had appeared outside his dual-element shield.
Ertaur snorted his nose and bellowed before charging at the shield with his horns pointed straight at it. Unlike the summoned creatures, he had complete autonomy when he used Blitz Steps.
Thus, Eratur decided to test the waters before attacking with all he had. Eren didn't like that his contract beast circumvented his orders by making the summoned creatures initiate their kamikaze attacks while he stayed behind.
'This mad bull wants to finish the old man all by himself.'
Eren smirked when he understood Ertaur's intentions. He decided to watch the show while his contract beast took the reins from him.
Bzzt. Swoosh. Boom.
Ertaur's attack made old Rey's water-element shield ripple as red lightning seeped into it. The shield soon started having tongues of red lightning streaks over it. It started destroying the green vines that were submerged in the shield.
"Aaaaaaaaaah. Listen to what your elders have to say, you devil."
Old Rey yelled at Eren with anger and horror mixed into his tone. The old man didn't call forth any more of his summoned creatures. He had decided to stake everything on sustaining his defense spell until Janos returned.
Eren ignored Rey's ramblings and focused his gaze on his contract beast who was gearing up for his second charge from a different direction. Eren could tell the beast was trying to locate the right angle to unleash his maximum power.
'What is that mad bull doing? The shield spell is the same from all angles.'
Eren looked at his contract beast confusedly. He thought that Ertaur had become mad trying to think about his charge so deeply instead of simply doing what he had told him to do.
Thankfully, he had someone in the pendent he was wearing who could answer this riddle for him.
'Hehe. You are wrong, Eren. Every spell manifestation can be divided into a few basic building blocks. They include mana, elemental attainment, the will of the person in the form of their mana sense or soul sense, and invisible mana flow. These things have to come together for any spell to manifest itself.
What Ertaur is doing right now is finding a point of contact in the shield that is most vulnerable to his attacks. There is a flow of mana in the spell that he is trying to keep tabs on. He is doing it with his animal instincts alone.
Don't underestimate the beats. Sometimes they can be smarter than most rankers.'
Alephee explained Ertaur's actions in brief. Since the bull was doing things on his animal instincts, the butcher couldn't get a read on him even though he could understand him mentally.
'The basic building blocks of spell manifestation, huh? Interesting. I suppose the mana circuits are also included in the list.'
Eren's trail of thoughts was completed by Alephee right away.
'Yes. Because spell manifestation starts when the mana circuits have done their job casting the spell. But typically, mana circuits are often overlooked when spell manifestation is considered.
You can tweak each of these basic building blocks individually or in unison to maximize your spells to absurd levels. Provided you know what you're doing. Otherwise, the spell manifestation will get destabilized and it would end up causing you harm.
What you are doing with your training is learning to control the flow of mana. You have already seen what a bit of improvement in that section can do to your spells. It would set you apart from the crowd one day as you keep on refining your control over the flow of mana.'
Eren watched his contracted beast attack old Rey's shield a bunch of times while chatting with Alephee. He wondered why she did not mention anything about the other building blocks of spell manifestation and ways to improve them.
After all, he was addicted to casting spells with better control than before, thanks to the mana circuits control training he was working through. The optimal mana flow allowed him to enhance the effects of the spells while minimizing his mana consumption.
As such, the butcher was interested in learning about ways to improve other sections of the spell manifestations as well.