Devil Arms

Devil Arms
Devil Arms are a series of demonic weapons that are manifestations of demonic beings that were slain in the past. They are also the souls of the demons have been killed, solidified into the physical world, hence that is why they are separate from normal weaponry, and are incredibly difficult to destroy. If they were hit by an atomic bomb dead on, they would only take minor scratches.

Feeding and relationships
Devil Arms primarily work with demonic energy, feeding off it to sustain themselves otherwise they will go berserk and eventually evaporate out of existence. However, in the case of Tekken, they can create substitute energies for them to absorb instead if the host does not have any demonic power, or gradually taint the host's energy with it's own to make their energy more suitable. In Nico's Case, he was a DPU Candidate, although he was unaware of it at the time. That alone made his SP unique, as well as edible for the Devil Arms, leading to his easier time using them. They make sure to take care of their hosts otherwise they will die, for the lives of the wielder and weapon are intertwined. If the weapon is destroyed, its essence recedes inside the host's soul to rebuild its physical form. It will let the soul of its wielder know when it is ready to return, and thus they will be able to call on it once more. The time frame for this however, differs depending on the Devil Arm.

While they feed off the energy of their wielders to stop themselves from vanishing, they also have their own power reserves, power of which they replenish either naturally (which is what they normally do with minimal energy leeching involved) or when they are offered by their user more and more power. It's like when a ravenous lion is offered a large pile of massive meat slabs, they wouldn't hesitate to gorge themselves on the prize. This has the advantage of boosting their attack strength, but one has to be careful as to not overuse their energy reserves otherwise they may fizzle out and die. Some Devil Arms are also more ravenous than others, thus it is important for Devil Arm wielders to know their feeding habits for battling. In Nico's case, he has various Devil Arms that each drain their own amounts of his energy, though his energy replenishes at a rate of which where he doesn't even notice, therefore he doesn't need to worry about this issue.

They also share a powerful symbiotic relationship, however it is more to the host's favour than the Devil Arm. As Biko once states: "When the host dies, so does the Devil Arm", what he means by this, is that their lives are intertwined, due to the Devil Arms latching onto the user's soul. Being a Devil Arm is a serious undertaking, for those that do are, in all sense of the word, on life support. Parasites. They cannot live without a host to house their essence. Therefore, if they find a worthy wielder, they can possess and control that wielder and make them do their bidding.

However, like with Nico and Tekken they can be controlled instead, eliminating the possibility of possession. However, it is very difficult for one to control a Devil Arm, it is essentially like trying to reign in a bunch of hormonal rampaging teenagers addicted to high grade drugs. Or trying to convince an arrogant tyrant that their ways are wrong. Thus, it takes considerable willpower to keep them in line. The fact that Nico wields several Devil Arms and hasn't lost himself is almost unheard of, and a testament to his mental fortitude.

Origins
Devil Arms originated within the DPU Era. Back then, Demons and DPUs ruled supreme over the humans in that time, and it was firmly established that no human could overpower a demon. Not only thanks to the physical differences, but humans beck then were like infants in terms of combat prowess, energy reserves, the works... at least, by demon standards. By no means were humans were weak, as even back then they had powerful creatures unlike those of current society to contend with for territory and resources. Normal monsters by the way. Their base monsters were the equivalent of the Abnormals in current times. But, there was a whole plane of distance between their strength and that of a demon's. An entire Kingdom's worth of forces would only take down few of the lesser demons, that was how the difference between them was.

However, an incident happened one day and changed the balance between humans and demons drastically. One human, during a conflict with a demon who'd caused the human much grief in the past, got lucky and managed to score a critical hit on the Demon he'd been fighting. The human had done it through the use of the demon's own weapon, which was a Hellblade, of which he had only gotten by sheer chance. Yet, it was that chance that changed things forever. That demon died, but before it could return to the non-physical plane to reform, its rage at the one who defeated it had become so great that its soul tried to possess the human, to overtake it's foe's will and use the human's body as a vessel. However, the Demon underestimated the Human's willpower, and because of that it's soul became subjugated by the human, manifesting its power as a weapon that the human used to great effect. The world's first Devil Arm.

Afterwards, other cases of humans becoming able to use Devil Arms occurred, Demons turning into weapons that they used for their own gain. Back then, the human's will to survive had been much greater than current generation humans, their willpower being born from constant struggle to survive as a species in an era filled with beasts that could cause mass genocide of their ranks without even so much as blinking an eyelash. Unfortunately, There were so very few who managed to succeed where this one human had done so, and many humans joined the demonic ranks as mindless entities, hell-bent on nothing but their own instincts. Those that survived and overcame the Demonic Souls to use their powers would remain hidden from society, only emerging when absolutely necessary for fear of being outcasted. Whenever their homes were threatened by zealous Demons or arrogant DPUs who thought they could have some fun with them for some time, these people would appear to challenge them. Devil Arms, in those moments, would prove to be just as lethal, if not more so, than the foes they fought, for at base strength they rivaled that of the demonic forms they once took. Therefore, their base strength always varied. However, through training and absorbing demonic souls, these weapons grew in power, gaining new abilities to make them even deadlier on the battlefield.

Methods for Control
There are several methods to controlling a Devil Arm, the first being Subjugation. Subjugation is where one imposes their will over the Devil Arm after it tries to kill them and take their bodies for its own means. Most of which revolve around chaos, death and destruction. Those are the things that excite demons the most. Normally, humanity would NEVER have a strong enough willpower to subjugate a Devil Arm, for their wills would be too powerful, too vast. It's like trying to compress a raging hurricane within a wine glass, nigh impossible. However, the nigh impossible isn't impossible, as there have been humans who have the mental fortitude to dominate the Devil Arms, earning the right too wield their power. Despite this being one of the most dangerous means, it is also the most fruitful. Devil Arms respect those with strength, the strength to do what needs to be done, the strength of one's resolve. They follow the laws of the jungle, therefore if they are proven to that their wielder is strong enough both in mind and soul, then they will follow that person to the ends of the earth. Not even caring about their limited lifespans. It has been recorded that a Devil Arm and Wielder could potentially live forever if their compatibility is high enough, for in those cases Devil Arms act like life supports to their hosts, keeping them in their prime with their power.

Another method is combat itself, a simple enough procedure. The wielder must defeat the demon on combat, killing it to prove his or her strength. Thus, the soul inside the creature will recognize that a potential wielder is within the vicinity and will try to possess them, latching onto their souls permanently while taking over. If the host's will is strong enough they can resist and dominate the Devil Arm, rendering it unable to possess them and reducing them to the role of a servant to the host. No matter what the method is however, Devil Arms will NOT follow a wielder who is weak of body or mind, they must have both otherwise they will take over and reduce the host to a demonic entity no better than a walking corpse.

However, one simply CANNOT wield another's Devil Arm. When separated, the Devil Arm will return to the rightful wielder's side. Not only that, but it will cause severe damage to those that do, potentially fatal. They will only acknowledge those that have passed its test, anyone else is just another body to cut open or smash to dust to them. Killing the original wielder won't be any better either because the Devil Arm is essentially a Demonic soul on life support. If it loses that support then the soul vanishes from existence, no exception. While Devil Arms value strength above all else, they also value strong loyalty o those that prove themselves. They will stick with their wielders through thick and thin, never leaving their side. They may get... rowdy, from time to time, however once they see that their wielder is worthy they will not listen to any other. Devil Arms may be troublesome to handle, but the benefits far outweigh the cons.

Powers and abilities
Devil Arms have a variety of powers and abilities, depending on the forms they took before becoming sentient weapons. There is a Devil Arm for many a Demon form, and some can be forged artificially (Rebellion, Ebony and Ivory) Although the method used is currently unknown. These powers are what makes Devil Arms so deadly and versatile on the battlefield, though their conditions for wielding them make using a Devil Arm exceedingly difficult if they do not meet their criteria.

In addition, no Devil Arm has the same power, each one is different and unique in their own ways. Their powers are set this way due to their previous forms before they became sentient weapons that devour unworthy wielders. Nico himself once remarked about how powerful the Devil Arm Alastor was when he was repairing a Dragon Vessel, twice as large as an average Zeppelin, that he had destroyed with Alastor, and how powerful a Devil Arm could be when used properly. Though, Biko does counter with the fact that Devil Arms are only as strong as their wielders, implying that even if they were really powerful, they would suffer if their users couldn't utelize their full powers effectively.

They also have a hidden power: the power to undergo Archdevilfication, which in the end results in them gaining a tremendous power boost as well as new forms called Archdevil Arms.

.