The reason Tannin reincarnated as a Devil was because there was a dragon species that could only survive by relying on the plants in the Underworld.
However, just as there are dragon species that need the plants of the Underworld to survive, there are also dragon species that are not suitable for the environment of the Underworld and need to grow in areas outside the Underworld.
In order to take care of different dragon species, Tannin often contacted Sirzechs and the others for help on a daily basis, thus owing quite a few favors.
If Tatsuma was willing to help, it would be a good thing for him, but...
"Red Dragon Emperor, since you are so actively offering help, is there something you want me to help you with?"
Tatsuma nodded. "Yes, I need you to help me with two things."
"Can you reveal the specific content?"
"Of course."
Tatsuma nodded slightly, holding up a finger.
"The first thing, I hope Dragon Mountain can cooperate with Akatsuki to establish a new branch in the Underworld."
"Akatsuki branch... No problem." Tannin agreed after a little thought.
He knew a bit about Akatsuki, it was an organization specifically for capturing evil spirits and wanted criminals.
Establishing a branch in the Underworld would be nothing more than catching stray Devils. For adult dragons, this was not a difficult task and was acceptable.
Tannin asked, "What is the other matter?"
"Help me cover for Sirzechs's side. I need to collect monster flesh and blood."
"?"
Tannin's mind suddenly froze.
As a former Dragon King, Tannin was a smart dragon. Precisely because of this, he was very clear about the potential meaning of Tatsuma's words.
After looking at Tatsuma for several seconds, Tannin finally couldn't help but break the silence first.
"Red Dragon Emperor, are you... serious?"
"Of course I'm serious."
"But..."
If you want to collect monster flesh and blood, wouldn't it be enough to just tell Sirzechs? Why bother doing it yourself?
Tannin's emotions were complex, and he thought of his earlier speculation again.
Could Tatsuma really be sick?
Noticing the change in Tannin's gaze and guessing what he was thinking, Tatsuma spoke, "I'm not sick, I'm perfectly normal. I mentioned the reason before. I developed some special magic that needs testing."
"Collecting monster flesh and blood is one purpose, and testing the magic's effect is also one purpose."
"I will heal the beasts' injuries afterward, this matter won't cause them any loss."
"With good luck, they might even be affected by my magic and become stronger."
"There's such magic?" Tannin was a bit skeptical about this.
"Of course there is. Do you want to try it?"
A flash of electric light appeared in Tatsuma's palm.
"Then... let's try it."
Tannin hesitated for a moment before agreeing.
At the instant Tannin finished speaking, a massive surge of Time energy enveloped him. Tannin's consciousness went blank. When he came back to his senses, the red lightning was already close at hand.
Boom!
[Congratulations! You have successfully defeated Tannin and obtained the Red trait: Dragon Bloodline.]
[Dragon Bloodline (Red): Training effect +1000%, physical stats greatly improved, Magic capacity greatly increased.]
A red training-type trait, not bad.
Glancing at the effect of Dragon Bloodline, Tatsuma took out a white trait from his storage and slapped it onto Tannin.
Tannin's aura rose sharply, the power within his body amplified.
Seeing that the situation was almost right, Tatsuma activated Myriad Phenomenon Rejection to heal Tannin's injuries.
A few seconds later, Tannin woke up from his coma.
"Just now, that was..."
Recalling what had happened before he fell unconscious, Tannin fell silent.
Although he was nominally a High-Class Devil, his true strength was definitely comparable to a Satan. Under prepared conditions, he was instantly defeated and knocked unconscious by a single move.
Such strength...
Perhaps even the former Two Heavenly Dragons were inferior, close to the legendary God of the Bible.
"I thought the rumors about the Red Dragon Emperor were a bit exaggerated. Now it seems I was too arrogant."
Tatsuma said, "It's a very normal phenomenon to have doubts about things that defy common sense."
"Incidentally, your luck is good. My magic just now activated your potential."
"Hmm? This is... How is this possible!"
Tannin finally noticed the changes in his body, a look of disbelieving shock on his face.
He was a Devil who had reincarnated by fusing with Mephisto Pheles's Queen piece.
Mephisto Pheles was a director of the Magician organization Grey Wizards and also the person with the highest magic attainment among Devils.
As Meohisto's Peerage member, Tannin knew a thing or two about magic.
Getting stronger after being attacked by magic seemed like nonsense to him.
But now that the truth was in front of him, no matter how much he doubted, he had to accept reality.
"I didn't expect such magic to exist."
"Of course. I never lie."
Tatsuma nodded without changing his expression.
"Tannin, this magic of mine is a special magic independent of the existing magic system. Many magic theories do not apply."
"In order to completely perfect it, I attacked the nearby monster tribes, assaulting them and collecting data for refinement."
"This matter has a significant impact. Before the magic is completely perfected, I don't want too many people to know."
"Especially Sirzechs's side. If he knew about this, there would be a lot more trouble. You should understand what I mean, right?"
"I understand." Tannin nodded with a serious expression.
Tatsuma's magic...
It wouldn't be an exaggeration to say it was a magic that defied common sense and overturned the entire world's structure. The fewer people who knew, the lower the impact.
"I will keep my mouth shut and won't tell anyone about this."
"That's good."
A look of satisfaction appeared on Tatsuma's face.
Because of Rias, Sirzechs had known for a long time that he could activate others' potential to make them stronger. But as long as Tannin didn't know about it, it was fine.
Both sides were doing their own thing, lacking key information, so there was no need to worry about exposure in the short term.
As for what to do if it was exposed later...
There will be a way when the time comes. At worst, just owe a favor and pretend nothing happened.
Glancing at the five Rainbow traits in the system panel, Tatsuma felt confident.
"Tannin, have you thought about the cooperation?"
Tannin nodded. "I've thought about it. I can represent Dragon Mountain in accepting the cooperation, but... if you cause too much chaos among the monsters, I might not be able to suppress the news."
"It's okay, I've already thought of a countermeasure."
Tatsuma repeated the method he had temporarily come up with.
After listening, Tannin was a little surprised.
"Is this really okay?"
"Give me the coordinates of a monster stronghold, and we'll know if we try it."
"Hmm... Then let's try it."
Tannin recalled the nearby monster strongholds.
As the leader of Dragon Mountain, Tannin's understanding of monsters was naturally higher than Rias's.
Excluding the monster strongholds that had already been attacked, Tannin quickly thought of a suitable target. Carrying Tatsuma and Est, he flapped his wings and flew towards the target.
With his Satan level strength fully unleashed, the surrounding scenery became blurred.
A few minutes later, Tannin brought Tatsuma and Est to the front of a cave.
Sensing Tannin approaching, over a dozen leopards with red stripes darted out of the cave.
"This is the Blood-patterned Leopard stronghold."
Tannin explained to Tatsuma and then landed in front of the group of Blood-patterned Leopards with the two of them.
"Tannin-sama, long time no see."
The leading Blood-patterned Leopard walked up, a wary look on its face.
"What brings you here today?"
"I received news that there are Satan-level terrorists attacking nearby monster strongholds recently. I came to check the situation and set up a barrier."
"Satan-level terrorists?" The Blood-patterned Leopard leader was stunned, a little surprised.
"You're not joking, are you?"
Tannin said, "Of course I'm not joking. To deal with this incident, even the Red Dragon Emperor has been dispatched."
"Everyone, please cooperate with our actions."
Tatsuma jumped off Tannin's back, releasing a faint pressure.
After upgrading his Satan Bloodline to Devil God Bloodline, his aura had become increasingly heavy. Even if he only released a little, it was still something these Blood-patterned Leopards couldn't bear.
Feeling the immense pressure coming at him, even without seeing a portrait of Tatsuma, the Blood-patterned Leopard leader still believed Tatsuma's identity.
"Red Dragon Emperor, please stop. We are willing to cooperate with your actions."
"I like smart leopards." Tatsuma nodded with satisfaction.