Evolution doesn't necessarily mean a change in the body.
I think handling tools or communicating with a group counts as evolution, too.
For example, humans became the dominant species on Earth by learning to use tools.
Forming a society and learning from one another.
In a way, the most important kind of evolution.
One such example.
“Well done, Little Squirmy! You’re already the big boss.”
Little Squirmy had started living in a group.
It began caring for its own children and forming a group with them.
Mini Little Squirmies could be seen behind it.
There were only four for now, though.
Whoosh!~
I boldly accelerated time by about four years.
Little Squirmy had evolved into a mammal, so it took a long time to give birth, but that was nothing compared to the ten thousand years I had.
Little Squirmy's gestation period was currently about four months.
The more it evolved, the longer its pregnancy became, but the group had already grown to dozens.
Once they had children of their own, their numbers would increase even faster.
“Heh. So many cute little things.”
It was quite a sight.
Just watching Little Squirmy and the mini ones swimming together made me grin.
It was all thanks to raising them as mammals.
Giving birth to live young instead of laying eggs.
That was important.
It strengthened maternal instincts, and the young could learn all sorts of things from their parents.
That would help them form close bonds, too.
Their survival rate would rise as well.
Whoosh!!~
After watching with satisfaction, I accelerated time again.
Ever since becoming mammals, their biological structures had grown increasingly complex, so evolution was slower than before.
Since I had to wait for their offspring to reproduce as well, they couldn't evolve in intervals of days or weeks.
Time acceleration was essential.
Accelerate.
Observe.
I repeated those two processes over and over.
When I returned to reality, I read books, looked up information, or exercised.
My ability to focus kept deepening.
My patience kept growing.
And so, another five years passed.
It was more exhausting than I'd expected.
Even with time acceleration, I had to keep observing changes in short intervals, while evolution gave me less of a dopamine rush than before and the amount of studying and exercise kept increasing.
But it was fine!
This was what I was best at.
Everyone else would drop out during these grind-heavy parts of a game, but I found them fun and forged ahead.
Yeoulrim was the same.
I enjoyed this process.
I took even better care of them.
Seeing Little Squirmy and its children grow so fast was reward enough. No, showing myself to them was the real reward.
Look.
[Projecting a form with light and telekinesis.]
“Pipyu~”
““Pipyu!~””
It was like this whenever I showed my avatar.
At Little Squirmy's warm welcome, the whole family would surround me and make adorable little cries.
I was about ready to die of a heart attack myself.
The mini Little Squirmies were just too cute.
More importantly.
[87pt of World Power acquired.]
I could gather World Power from the whole Little Squirmy family.
The mini Little Squirmies generated only a small amount, but together it wasn't insignificant.

“All right! Let's all play together.”
Before I knew it, I was grinning.
I wasn't supposed to be this kind of person.
After hugging each of the mini Little Squirmies in turn, I swam and played with them, getting to know them better.
*
I accelerated time by another five years.
After consistently inducing mutations in the offspring and waiting, one of them appeared that could use mana to shoot a wave from its mouth.
I taught Little Squirmy this trait, too.
This should make it even more likely to survive.
Another five years.
Little Squirmy had grown as big as me.
Broad, flat arms had appeared along its sides.
Little Squirmy's children also flourished and became independent, giving rise to several different groups.
Whenever Little Squirmy ran into one of its children's groups, it would stroke the group's leader on the head with its tail or broad, flat arm.
It felt a lot like the way I stroked Little Squirmy, and this behavior became a way of establishing rank within the species.
This time, ten years.
Around then, something astonishing happened.
Little Squirmy began using mana in earnest.
Its physical abilities had increased, and it had begun using a new kind of magic.
Creating waves.
It was astonishing.
Because I hadn't induced this.
I'd only passed on the ability of an individual that had learned to shoot waves, but after that, Little Squirmy learned a new kind of magic all on its own.
More astonishing still, it hadn't learned a spell and then cast it.
“When did it grow an organ like that?”
That was the power of its body.
A new organ had formed inside Little Squirmy's body, one that had evolved to use mana as its power source and produce a specific kind of magic.
Mana synthesis.
Mana consumption.
With those two traits increasing its mana supply, it seemed to have developed this organ to make use of it.
So.
A mana storage organ.
A magic-casting organ.
Two organs in total had formed.
I didn't know how it would evolve from here, but it was clearly no ordinary creature.
I'd have to keep watching to see what happened.
Whoosh!~
I accelerated time another five years and watched how things progressed.
Little Squirmy had gained more spells and could now use three in total.
The number of spells didn't increase easily.
Instead, its spellcasting skill improved day by day.
As a result, the spell that had only created waves evolved into a powerful technique that created small whirlpools.
It used those to sweep up other fish, then shared them with its children.
However.
“Everyone's spells are a little different.”
Little Squirmy's descendants were the problem.
As Little Squirmy evolved, a generation of its descendants appeared that could use magic, but the spells they used varied slightly from individual to individual.
Some fired streams of water mixed with waves.
Some created a large number of bubbles that burst like explosions.
Some momentarily strengthened only their tails and swung them.
Even when they used the same spell, their methods, efficiency, and power varied.
They could only use one or two spells. They couldn't handle three or more like Little Squirmy.
This would probably improve as they evolved.
“This won't end up going wrong, will it?”
Around then, I started to feel uneasy.
Having magic manifest inside the body was a build I hadn't tried many times. Magic could be studied and learned later, then put to use.
You might ask if that wasn't a good thing.
But they might end up getting used to only the spells they had.
Some might rely on their own magic and neglect using tools.
I couldn't say for sure since I hadn't properly researched this build, but it made me nervous.
“In the game, I once made it so they didn't poop, and it led to weird cases where they didn't distinguish between sexes or got their holes confused, lowering the birth rate….”
I was worried about what might happen.
In case there were other problems I didn't know about.
Should I undo it now, or leave it alone?
“Pipyu~”
Just then, I saw Little Squirmy diligently using its magic.
Its bright smile as it watched its own magic softened my heart.
“Well~ A path that's already been completed is boring.”
Let's give it a try.
The possibilities were endless.
If there were disadvantages, there were advantages, too.
It could cast magic instantly, with far greater power and efficiency than ordinary spells.
That alone was incredible.
I'd just have to keep watching.
*
After accelerating time by another five years.
[Pipyu!!~]
Its voice carried a wave.
Little Squirmy's cry, which had once been simply cute, had transformed into something transcendent. It was majestic and mysterious, yet had a refreshing clarity to it.
Its thin, threadlike voice stretched out, making my mind feel as though it were dancing.
The wave was so intense that it kept echoing in my mind.
It felt like it was ringing out again and again.
It was mysterious just to listen to.
It was enough to make me shiver.
In fact, little fish would often flee far away just from hearing its cry.
“My Little Squirmy. You've grown up so fast.”
It wasn't just its voice that had changed.
It must've been eating well, because Little Squirmy had grown into a plump, four-meter giant.
[Pipyu-uuu!!!]
Wooooong!~~~
Around then, something amazing happened.
One day, Little Squirmy's voice, carrying a wave, rang out across a vast stretch of ocean.
“Pipyu!”
“Piiii!”
Its descendants began gathering from far away after hearing Little Squirmy's voice.
Their intelligence.
Their strengthened magic.
Those two things working together had produced this effect.
To have developed this much already at the fish stage—it was far faster than in the game.
However.
“Is it planning to start a war?”
The entire species, drawn by the call, gathered in orderly formation in front of Little Squirmy and waited.
They looked quite solemn.
Why?
[Pipyuuuu!~]
I soon found out why.
Having gathered hundreds of its descendants in one place, Little Squirmy moved to the front, like a vanguard leading an army, and headed somewhere.
And that direction was...
“That's where the strong ones live.”
It was home to powerful predators.
I hadn't really explained it before, but Yeoulrim was home to many native life-forms.
Among them were quite a few advanced species that already lived in groups like Little Squirmy. And in that area...
Lizards?
Lizardmen?
A bizarre life-form with four tentacle-like limbs and a crocodile's head lived there.
Let's call them “Agmen” for now.
They were the rulers of the nearby sea.
They were clever enough to pick up stones and throw them, or bind their enemies tightly with their long limbs and tear them apart with their crocodile-like jaws.
They were so strong that most fish wouldn't even dare challenge them.
In other words, apex predators.
Or so they had been.
“Is it going to fight those guys!!?”
I couldn't believe it.
Little Squirmy was heading for the Agmen's habitat.
Since I focused only on the important moments and let time acceleration skip everything else, I had no idea Little Squirmy wanted to go to war with them.
I was taken aback, but...
It made sense.
Little Squirmy had once fled from the Agmen. Quite a few of its kind had also been captured and eaten by them, so they had a deep-seated grudge.
Their territories were close, too, so Little Squirmy must've thought the damage would only get worse if it left things alone.
“W-what should I do?”
I was getting nervous, too.
A war that would determine the fate of the species.
This… isn't going to go wrong, is it?