Krune, of course, still doesn't know about this awesome nickname.
The Lightning struck Krune's six Spiritual Energy Meridians. Immediately, they started to work at full power. Still, there was too much energy to be absorbed and converted. If this continued like that, he wouldn't be able to hold back anymore.
'I have to redirect the energy somewhere. But the problem is, the Heavenly Tribulation is targeting me, it definitely won't go anywhere else.'
Sparks flew everywhere, Krune energy body was almost disappearing, and his core would soon be affected. Suddenly, Krune had an idea.
'I need to send the energy somewhere, but it can only target me. In that case, what if I send it directly into my universe foundation without waiting for conversion? Other than the planet itself, my universe is basically void. There should be no problem in releasing all the tribulation power there. After all, the void is also considered to be me.'
Krune didn't have time to ponder about the pros and cons, and he had to act now. Krune immediately stopped the converting of energy process and opened his meridians fully to let all the energy pass through. All the Lightning seemed to have found a path which it could follow and rushed inside. As soon as the tribulation lightning appeared in his universe foundation, it started to rampage around. Fortunately, it was all void, there was nothing to be destroyed to start with.
Krune kept absorbing more Lightning, and a few moments later, all the energy of the tribulation was now flashing all around his universe foundation. Krune knows that this is just the start, and he can't simply leave the tribulation lightning moving around freely in his universe. This is a Heavenly Tribulation, it won't merely disappear, and it will keep running around until it finds a target.
Krune then focused on his universe foundation. Here, he is a god! When the Lightning first struck, Krune had initially used his energy meridians to convert it into spiritual energy. Only after noticing that he wouldn't be able to convert everything did he open his channels and let the Lightning go through. Fortunately, he had already restored almost all his spiritual energy before it happened.
Krune pondered for a bit. Unless the tribulation lightning finds a target, it won't go away, and there is only one thing that can be used as a target in his universe foundation. His planet!
'But this shouldn't be a problem, I don't need to guide the entire tribulation at once to strike my planet, I can do that slowly.'
And so he did. With the spiritual energy available to him in his core, he started to bait the tribulation lightning everywhere until it got separated in various small tribulations. Slowly, he guided one of them to his planet.
'This is the moment of the truth.'
The lightning tribulation seemed to have smelled something and rushed straight to the planet. The planet wasn't big to start with, even though the interior of the core space is warped, so it is much bigger than the appearance from outside, it had its limit. So Krune's planet wasn't much bigger than a few kilometers. The tribulation lightning then struck it directly. Immediately, the entire world seemed to have lightning sparks running all around its body.
Krune's soul wasn't having a good time either. Lightning element, especially one made of pure spiritual energy, is very effective against soul forms. With this one single strike, the pain that Krune felt wasn't the least bit inferior to when he first started breaking his core down. Fortunately, it was still bearable.
After a few minutes, the Lightning finally lost it's power and disappeared. Krune was feeling bitter. This was only the first one, and he had over a hundred strands of Lightning that he left running around in his universe. But he quickly made his mind. He needs to get over with it soon. Otherwise, the tribulation might find it's way to his planet and strike all at once. If that happens, there won't be even a trace of Krune's soul after that.
Lightning after Lightning struck the surface of Krune's little planet, but this situation wasn't without rewards. Krune's soul is being tempered even further now. Every time one lightning struck, he would go through an unimaginable amount of pain. Still, he could feel the power of his soul, strengthening bit by bit. He was familiar with this feeling from when he was breaking down his core.
Five bolts of Lightning, ten bolts of Lightning, twenty bolts of Lightning, fifth, eighty, a hundred. Krune was already on the verge of fainting when finally, the final strand of tribulation lightning was guided to his planet. Krune's face showed determination, and he faced the last lightning head-on! That's right, Krune knows that the Lightning also helped his soul tempering, so he decided that the last strand would fall directly in his soul.
"I said I was going to eat you, and I will keep my word!"
This time, Krune really felt he was going to die. But it wasn't long before the lightning power finally ran out. Krune could finally let out a sigh of relief.
'It's over.'
Just as he was about to start meditating to recover himself, that feeling of being one with the world returned.
'This... That's right, the golden core formation!'
Krune was right, he could feel the energy of the world again. It was something different from any other energy, spiritual energy included. It started to congregate in the place that he had prepared for his future golden core, but suddenly, something unexpected happened.
"The hell?! This thing isn't golden at all!"
Krune had heard from Ruik that his own future golden core was also golden from the start. It's just that the golden color it had was very weak. From what Ruik heard from other demon beasts, this is the normal process. The higher your stage in the Foundation Establishment, the stronger the golden color in the golden core becomes. It seems that when you arrive at the 9th stage, the golden core will be completely golden, showing that you are ready to enter the Core Formation realm.
The problem is, Krune's future core wasn't golden. In fact, it didn't have just one color. His future golden core, which isn't golden to start with, looked more like a rainbow.
"Maybe the heavens felt pity of me and brought some candy for me to eat."
Of course, that was just some bullshit Krune thought in passing. There was no way such a thing could happen. But still, why is his core so... colorful? But it wasn't over, just as the core was about to be completely formed, Krune felt the power of the tribulation lightning again. It turns out that his planet was struck by Lightning so many times that it had kept some of it in its interior. Just a moment before his future 'rainbow' core was finished, that strand of Lightning hit it.
Krune was alarmed, as soon as it was struck, it started to tremble and jump all over like it was popcorn. Krune could only pray in his heart.
'Please don't break, please don't break, please don't break...'
If his future rainbow core broke, his Foundation Establishment breakthrough would most likely be considered a failure. And the outer core would be destroyed too. Only death awaits him if that happens.
Fortunately, after a few minutes, it stopped jumping around. It regained its rainbow-like color, and the world energy finished its formation. It was now lying quietly in the center of Krune's planet core. But there was something different about it now, one could see some lightning sparks running around it.
"What kind of situation is this? First, I get a child's candy as my future golden core. Well, not golden anymore, though, and now this candy has Lightning running around it. I might as well pretend to be a clown and give it to the first kids I find beside the streets. Even if the Lightning doesn't let them eat it, it will still look like a fun toy."
Of course, such thought was basically done because of Krune's gloominess. He couldn't really give his future core away like that. It's just that he had to go through so much shit to complete his Foundation Establishment breakthrough that wanted to vent somewhere.
Before, Krune had paid a few visits to the nearby villages of the Katiu forest secretly. Coincidence or not, he found out what a clown is during one of those visits.
'It might have something to do with my foundation, the spiritual energy in my little universe is also rainbow-like, so this is probably the reason.'
Krune then put those thoughts behind his mind, he looked at the rainbow core, and it seems that it won't do anything for the time being. So he decided to go back to the spiritual vein lake.
On the way, he met with Ruik and Lakin.
"Master, you survived! That's great!"
Ruik also commented.
"Now then, you have finished your breakthrough, so our contract is over. I think that a Foundation Establishment is pretty good for cultivation too, so what about give yourself to me?"
Krune just laughed it out.
"Give myself to you? Does it mean you fell in love with my awesomeness? I'm sorry, but I have a fiance already."
Ruik immediately went red from anger.
"Scram!"
He turned back and entered the cave again.
Both Lakin and Krune laughed even harder, Lakin looked back at Krune and asked.
"Master, is everything over? Is there something you need help with?"
Krune was happy with his concern.
"I'm okay, except for the fact that I feel like a pile of shit, I'm pretty much fine. Let's go back to the spiritual vein lake, I need some time to recover."
After returning to the spiritual vein lake, Krune went to find Ruik straight away, and Lakin followed out of curiosity too. He then explained about his situation and how his future core looked like some rainbow candy with Lightning around it.
Lakin didn't know much about it to start with, so he just listened. As for Ruik, his eyes looked like he was seeing an anomaly.
"I know quite a few Foundation Establishment beasts, but all of us have the same type of golden core. The only difference is how much golden they are depending on our cultivation stages."
Ruik pondered for a bit and then continued.
"But I must remind you that Katiu Forest isn't a big place to start with, and there are way too many things out there that we don't know. There might be some other Foundation Establishment cultivators with a situation like yours. It was the first time I've heard about a Heavenly Tribulation falling before the Core Formation realm. Still, due to the lack of information we have here, it could have happened outside."
Krune agreed with his train of thought, there is now one more reason for him to leave. He then went ahead with another question.
"So, how this 'nurturing the golden core' works? Do I need to cultivate as usual, or is there some secret to it?"
Lakin also paid attention to this question. Thanks to his master, he really has a chance at the Foundation Establishment too. Ruik then looked at him and answered.
"There is. In fact, this isn't a secret, and you would find out about that sooner or later. The core in the center of the foundation can be nourished by sending spiritual energy directly into it. Once it feels the presence of spiritual energy, it will absorb the energy by itself. You just need to keep applying more spiritual energy until it stops absorbing. That is when your future core is ready to breakthrough into the next stage of the Foundation Establishment. Of course, you can't neglect your foundation either, try to remember what I said about my island in the lake foundation."
Krune pondered a little and found this memory. Ruik had said before that the lake holds the spiritual energy. It is then used to strengthen the island foundation. When the island gets sturdy enough, you can breakthrough into the next stage. Krune then waited for Ruik to continue speaking.
"You can think about it as preparing the foundation for a natural calamity. The breakthrough of each stage comes followed by a huge explosion of spiritual energy. If your future core or your foundation can't resist it, it will break apart. Your planet foundation is definitely top-ranked, so it should take even longer to improve it due to its size."
After hearing that, Krune asked again.
"So, which one should I nurture first, the foundation or the core?"
Ruik answered straight away.
"The core should be first since it is very fast. Although the planet will take a long time to be reinforced and stabilized, the core inside it doesn't need any of it. The core is different from your foundation. Take my future golden core as an example. It kept absorbing spiritual energy for an entire week without stop. But after that, it never accepted spiritual energy again. If you want, you can do it even faster, you just need to gather more spirit stones and suck then dry. As long as the future core has enough space for spiritual energy, it will accept everything."
"If I calculate the total spiritual energy that I used to fill up my golden core, I guess 200 to 300 Rank One spirit stones of middle or high quality should be enough."
Krune mentally noted down all this information. It wasn't that complicated in the end. Basically, nurture the core, then nurture the foundation, and finally, breakthrough to the next stage.
After conversing for a little longer, Krune went to the side of the spiritual vein lake and started to recover himself. He decided to take a few days of break to relax a little and think about his next steps.
After a week, Krune was back at peak condition. He decided that he will first gather some spirit stones from the nearby spiritual veins and get over with the first stage of his rainbow core. Krune had utterly given up the idea of using only the natural spiritual energy to feed his rainbow core or his planet foundation. He is a wisp, even though he is at the Foundation Establishment now, he only got another ten years of life span. He is four years old at moment, which means that he only has another sixteen years to breakthrough the Core Formation realm bottleneck.
He also wanted to try out the differences of being in the next realm. Exactly how stronger has he got? How better can he control his spiritual energy after the last tempering of his soul? His Divine Sense is out of the charts, and no one at his level has a Divine Sense as powerful as his. So he needs to test if demon beasts at the same cultivation level as himself can detect it. Finally, he has to stabilize and reinforce his foundation too. Krune can feel that the rainbow-like spiritual energy in his 'universe' isn't flowing smoothly yet.
In that case, what else is better to achieve all of that other than battle?