Riser Phenex? DXD SI. Multicross?

Let's go back a bit in time, to how it all began...

[Congratulations! You have died...]

[You have been chosen to reincarnate with Template Systems.]

[You will receive templates as well as items from the entire multiverse.]

[You will have 5 slots available to absorb the abilities of your Templates.]

[You will receive a dimensional subspace, where all items will be stored; once taken out, they cannot be put back.]

[You will reincarnate as Riser Phenex! In Highschool DXD. When you are 3 years old, memories of your previous life will be released.]

[This system will not provide any missions!]

[You will receive any rewards when there is a significant change in the world or history.]

[The Template System will also give you items, including Essences and even Devil Fruits. The Template abilities will have no weaknesses or deformities gained through appearance changes.]

[For example: if you have the Template of Goku Xeno in Super Saiyan 4, you won't gain the Oozaru form or even his tail, but you will have transformations from SSJ1 to SSJ4.]

[If you gain an item like the Devil Fruit, and then eat it, you will gain the weakness, such as being unable to swim. Once dead, the Devil Fruit will disappear from the world.]

[Upon arrival, you will receive 3 unique Templates and 3 unique Items.]

[Your previous life will not be erased but will be softened in your senses so that there is no pain or anguish during your past life.]

[You can take 1 item per week in loots, including money or even salt. Each month, you can take Character Templates.]

[Good luck!]

**

With these words appearing in a dialogue box amidst the darkness, everything went black. In an instant, I was launched, at high speed as if in a futuristic FTL ship!

Zhoop!

In another all-black setting!

**

[Boost!]

**

"Urgh!"

My head felt like it had taken a very strong blow. In another instance, a dialogue box appeared, notifying me of what had happened.

[Completed! Seal Unlocked!]

[Receiving Starter Package!]

[Acquired Alchemist Roy Mustang!]

[Acquired Sabo!]

[Acquired Lucifer MorningStar!]

[3 Items acquired, Essence of the Blank, Gura Gura no Mi, Essence of the Archmage]

Riser Phenex was in absolute shock at seeing what he had obtained in his first loot. Clearly, after 3 years without taking any Templates, the 3 items and 3 templates were much better than usual.

Thinking to himself, Riser then checked what the abilities were in each item he had gained.

["Show me my items and templates."] thought Riser, looking calmly ahead, waiting for what was to come.

[Templates]

[Alchemist Roy Mustang! - 30%]

[Sabo! - 5%]

[Lucifer MorningStar! - 0.5%]

[Empty]

[Empty]

-

[Inventory]

[Essence of the Blank, Gura Gura no Mi, Essence of the Archmage]

**

[Boost!]

**

["Give me the Essence of the Blank, Essence of the Archmage."] – Two items quickly appeared, one crystal-clear white and the other blue, shining so intensely it seemed like they were lighting up a lamp.

Riser didn't waste time and drank the White first; as soon as he finished drinking it and waited for a while, he drank the other. And he waited for a certain time as well. Riser felt like his body was losing a weight that shouldn't be there, as if something was preventing him from moving freely or even thinking freely.

Then Riser read the information on the Essences.

[Essence of the Blank!

By taking this essence, you gain only one benefit:

Your potential becomes limitless. You can learn any discipline or set of skills, even if you shouldn't be able to, without forgetting them and practice them to mastery, no matter how many you learn. Any skills you have from other Essences will increase whenever possible and develop in ways beyond their initial purposes.]

[Essence of the Archmage

By consuming the Archmage's essence, you gain various benefits.

Perfect memory with infinite storage.

Genius-level intellect.

Ability to learn any "magic," even unique ones, by seeing it once or understanding enough about it. This includes things like Ki, Chakra, soul power, etc.

Possess a supernatural reactor that can adapt to any supernatural energy to power spells, enchantments, powers, etc. This reactor provides a constant supply of energy that will grow over time; now you can use high-consumption abilities with wild abandon and still not be much worse off after a few hours.

Can teach systems to others, even if they previously lacked the capability.

Manipulate entire systems or combine them through experimentation.

Capable of casting any spell as long as you have energy and it doesn't require any extra elements, such as focus or materials. The time required to cast, if any, remains.]

"Wow! Simply wow! Unbelievable! Impossible to believe! So I can really be strong in this world! Probably with the Lucifer lineage too. He he he," thought Riser, unaware that it wasn't the Lucifer he was thinking of.

["Well, show me each Template now!"] said Riser in his childish mind.

[Roy Mustang!]

[Flame Alchemy - Even among the elite State Alchemists, Colonel Mustang is a particularly skilled alchemist, well-versed in standard physical transmutation, experimental theory, and biological alchemy. However, the brilliant skill that earned him a state license, national notoriety, and "hero" status during the Ishval Civil War is his extraordinarily powerful fire-based combat style.]

[Charisma (Ranking D): Natural talent for leading a military force. In this case, Roy Mustang specialized in military battle.]

[Sabo! - 5%]

[Ryusoken - In his adulthood, Sabo became a master of the Ryusoken fighting style, which revolves around the use of his fingers, which he calls "claws." His grips are strong enough to break armor, large swords, artillery, and even skulls with immense ease and still come out unscathed; he claims his fingers are like a dragon's claws and uses Haki to enhance the grip's strength.]

[Devil Fruit - Mera Mera no Mi with no weaknesses. Sabo ate the Mera Mera no Mi, a Logia-type Devil Fruit, allowing him to create, control, and transform his body into fire at will.]

[Haki

Busoshoku Haki

Sabo showed great mastery of Busoshoku Haki, which he can imbue in both his arm and weapon. His Busoshoku Haki is strong enough to break the armored right arm of Burgess, infused with Haki, as well as Diamante's sword. His mastery of Busoshoku is superior to Bastille's, as shown when the Vice Admiral tried to strike him with sword blows enhanced by Haki; not only did Sabo manage to block his Samekiri Bōchō, but he also destroyed the entire blade with relative ease.

Kenbunshoku Haki

He is highly skilled in the use of Kenbunshoku Haki, as shown in the anime when he felt that Luffy's Haki had become

 weak during the battle against Doflamingo and when he dodged several bullets fired at him.]

["Well, you can't choose, huh. Unfortunately, I didn't get Whitebeard's Template and got the Mera Mera no Mi. But what can I do? I have to stick with Luffy's brother. Hmph..."] thought Riser, knowing that if he ate the Devil Fruit, he would inherit all the weaknesses.

Continue....