Although Seimei might not need these eye drops to prevent permanent loss of ocular power and blindness due to overuse of the Mangekyo Sharingan, seeing his father's concern for him, he felt a distinct warmth in his heart.

He felt he was lucky to encounter such a warm family right after his transmigration.

Otherwise, in this chakra beast-infested ninja world, he might have become pre-dinner snacks for some random chakra beast before he could even reach an orphanage.

He was fortunate to be picked up by Tobirama in time.

Senju Tobirama might be a little grumpy, ruthless, and filled with dark humor, but he was still a caring father who helped Seimei become who he is today.

Just look at him.

He had worked tirelessly for five years to find a way to prevent the issue of blindness that came with the use of Mangekyo Sharingan.

It was obvious that he had to have overturned the entire Fire Country to find the right ingredients and spent many nights figuring out the exact way to counter the Mangekyo Sharingan's blindness problem.

Since Seimei had a rather pure Otsutsuki blood running through his veins and a cheat-like system, he was bound to unlock Eternal Mangekyo Sharingan.

He wouldn't have to fear blindness.

He could use the full power of Mangekyo Sharingan without fearing depletion of ocular power.

In other words, he wouldn't have to use his father's special eye drops to prevent blindness.

But that didn't mean Seimei had no other use for these eye drops.

According to his father, each drop of this special potion had an immense amount of vitality and Yang Release chakra hidden in it.

If the wielders of Mangekyo Sharingan or any other Dojutsu applied these drops to their eyes, the potent Yang Release chakra within them would accelerate the generation of ocular power. If they used it regularly, the total amount of innate ocular power of the eyes would also increase.

It meant that even if the user of Mangekyo Sharingan depleted almost all of their ocular power, a few days of rest and use of these eye drops will replenish the lost ocular power.

In the long term, even the power of their Mangekyo Sharingan would increase, making the ocular techniques and Susanoo even more powerful.

What did this mean?

It meant that even if Seimei directly awakened Eternal Mangekyo Sharingan, these eye drops could still improve his Sharingan's power, leading it to a higher level of evolution.

The ultimate evolution of Sharingan—Rinnegan.

These eye drops would significantly shorten the time he required to awaken his Rinnegan. For Seimei, this was great news.

Of course, the use of this potion didn't end here.

This potion was a great discovery, almost like a divine elixir, for the Uchiha ninjas, who had awakened Mangekyo Sharingan and were troubled by the blindness problem that came with it.

Those ninjas would pay any price to buy these potions, filling the Senju clan's coffers to the brim…cough…!!!

He meant he wanted to exchange these potions with his fellow red-eyed, Dojutsu-wielding comrades to ensure they never went blind while protecting Konoha with their ocular techniques and Susanoo.

According to his father, even if Seimei didn't believe in the Will of Fire, he must use the Will of Fire to brainwash and control…ahem…he meant he must use the Will of Fire to make his fellow ninja's heart burn with passion, love, and spirit of sacrifice for Konoha.

So, yeah, these potions could bring the Senju and Uchiha clans even closer, further washing away a good portion of still lingering resentment and enmity that the Uchiha clansmen harbored because of their conflicts during the Warring States Period.

Plus, his dear friend and rival Reina, a talented Uchiha Kunoichi, would surely awaken Mangekyo Sharingan sooner or later.

For the sake of friendship and out of concern for her health, he must gift some of these potions to her.

He had no ulterior motives.

Cough! Cough!

He just wanted to help his friends.

Anyway, that wasn't important right now.

His focus should be on the potion.

Due to Seimei's presence in this timeline, Tobirama went into full-on scientist mode and ended up creating the first successful prototype of a potion that would be very beneficial to the Mangekyo Sharingan users.

This would undoubtedly make the Konoha and the Uchiha clan far stronger than before.

Without his existence, Tobirama would have never bothered with creating this potion.

But now, Seimei's existence was like a flap of butterfly wings that would create a storm that would cause several major changes in this alternate universe's timeline.

As for how everything would unfold from now on…

Only time could tell.

---------------

As much as he marveled at his father's genius, Seimei had a lot of questions about the potion he wanted to ask.

He was also a potioneer, and a rather good one at that.

So, he understood that creating such a potent potion would require equally potent material that contained great vitality and powerful Yang Release chakra.

In the original Naruto anime, only Hashirama cells and White Zetsu cells could contain such powerful vitality and Yang Release chakra.

However, the Hashirama cells were far too active and almost uncontrollable. Meanwhile, almost no one was aware of the existence of White Zetsu until the very end of the series.

Even Orochimaru could only think of using them as glorified sacrificial vessels for his Edo Tensei or Summoning: Impure World Reincarnation Jutsu.

He hardly thought about other uses, wasting the potential of the White Zetsu cells.

However, this world was different.

This world had many extraordinary minerals, incredible herbs, and unique chakra beasts that could be used as materials to create unique artifacts, weapons, potions, medicines, and other mind-blowing things.

The problem was that there were too many ingredients and raw materials. Finding a suitable material that met the criteria for creating a brand new and unique potion was too hard.

His knowledge of potion materials and potioneering was still very limited.

So, he directly asked, "By the way, what did you use as the core material for this potion? I can't think of anything that can radiate such a strong vitality and Yang Release chakra."

Tobirama's reply was fast. "It was the core of an A-rank Treant."

Seimei raised his right eyebrow and asked, "Those annoying tree monsters that just won't die even if you burn them with Fire Release techniques and controlled, degraded versions of Wood Release?"

"I thought they were B+ in danger rating?"

Tobirama shook his head and answered, "No. Not those fake Treants, but true Treants."

"These True Treants are born with enough power to crush an average C-rank chakra beast. When they grow up and mature, they reach A-rank and turn into True Treants."

"They have powerful vitality and Yang Release. Their Wood Release innate skills are far more powerful than the normal Wood Release Kekkei Genkai that most Senju clan ninjas had awakened. Of course, it's weaker than my brother's Wood Release."

"But the Wood Release of these True Treants was the most powerful variation of it I have ever witnessed among the chakra beasts except for the S-rank Treants."

"In fact, to handle an A-rank True Treant, you must have Kage-level power at the very least."

"But since 85% of them reside in the Great Verdant Forest, one of the Forbidden Zones within the Fire Country, people usually don't encounter True Treants."

"This caused their danger rating to drop to A-rank."

Then, Tobirama paused for a second before continuing.

"Alright, back to our current topic."

"I have recently discovered that the core and the inner wood material of these tree monsters have immense vitality, Yang Release chakra, and restorative factors."

"So, I used the energy from the A-rank chakra beast core, the inner materials of the True Treant, and a few other auxiliary materials to create these potions."

"Now, I only need to figure out the precise ratio of the mixture to maximize this potion's power, which you can use as an eye drop to prevent blindness or loss of ocular power due to the overuse of Mangekyo Sharingan in the future."

Seimei nodded and said, "I see."

Then, he asked, "Can I see the experiment log?"

Tobirama nodded in affirmation and said, "Sure."

After that, he brought out a thick stack of documents, which were bound into a book, and handed them over to Seimei.

"Check it, and let me know if there's something you don't understand," said Tobirama. "I will also check how far your potioneering skills have reached after that."

Seimei nodded, took the research log, and said, "Thank you, father."

And so, Seimei began to flip the pages silently, trying to imprint every single research detail in his mind.

On the side, Tobirama was conducting his own research.

The duo of father and son was engrossed in their own work.

For the next couple of hours, only the sound of flipping pages, boiling potions, and test tubes could be heard within the main research room of the hidden base.

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