Kurikara

The Kurikara is a Devil Arm forged by the two halves of Chrono Roth.

Tinsaiga
Forged from the scale and tooth of Chrono Roth and consecrated in his blood, the Tinsaiga was the forerunner of the Kurikara, and roughly one-half of the blade's truest potential. It was an Odachi that appeared to have seen its fair share of battles. The saya's fuchi was gone, in addition to the kashira, and the Tsuka-Ito was frayed and unravelling, the tsuba was cracked and missing chunks, and the blade itself looked as though it hadn't been sharpened or repaired since the day it was forged.

The sword seemed to evolve when it was in the hands of a "worthy" swordsman. It gained no physical weight, but the blade lost all physical imperfections, and easily quadrupled in width and length, and gained unrivalled cutting power. While in this superior state, the sword also granted its holder the ability to control ice magic, at no mana cost. This ability was nearly all-powerful when the sword was used by its forger, extending to nearly every and all form of ice magic, giving him total control over even the weather, the spells of his enemies, and even the life force and minds of those who have a particular affinity for ice and frost.

In addition, the sword later had the ability to steal the souls of its enemies, to either save their lives from a horrible fate, or absorb their souls to fuel the blade's power. Those who were absorbed found themselves trapped in a barren and empty tundra, where snow never stopped falling, but the temperature stayed at around 70°F(Room temperature). The sword could also be used to cut bits and pieces away from a person's soul, to remove afflictions of the mind and the spirit. This was an extremely lengthy and draining process, however, and comes with no small amount of danger. It could take days or even months depending on what was being cut away, and if the process was interrupted at all, then both parties could die instantaineously. Even beyond this, there was no guarantee that the process would end in success. When it did work, however, it worked forever. Whatever was cut away stays away, and can never return under any circumstance. Even the power of a god as mighty as The Writer would do NOTHING to return the soul to its whole form again.

Ketsumei
Forged from the bone and mask of Wrath and consecrated in his tears, the Ketsumei was the forerunner of the Kurikara, and roughly one-half of the blade's truest potential. It was a wicked scythe with a bood-red blade and an edge made from sterling silver, and a handle made from ebony. In stark contrast to its sister weapon, the Ketsumei seemed to be forged from elegance itself. It was impossibly ornate, and crafted in such a way that it should have snapped if one ever tried to swing it with any sort of force, and yet it never seemed to weather in the least.

Also unlike its sister weapon, the Ketsumei never changed shape or form in any way, no matter who was using it. It did, however, grant its wielder the ability to use fire magic in a way that rivalled the Tinsaiga, and when used by Wrath, the weapon allowed him the same degree of control as the Tinsaiga gave to Chrono.

In addition, the scythe eventually gained the ability to drain the blood from its enemies, healing the wounds of its holder and slowly draining an opponent dry. This ability could be used from range as long as the target was within eyesight, however it would be halted if Wrath's concentration was broken.

Fusion
While once the two weapons were separate, when their masters forged, as did they, forming the mighty Devil Arm Kurikara. Now a beautifully crafted katana, the sword granted its holder mastery over fire AND ice at no cost, but never to the degree possible with the separated weapons. It can still sever souls and even destroy them, and it can still use the blood of its foes to heal its holder, but it can no longer drain blood from range, or reap souls from range. The sword also has the ability to force its blade to take on any size of any dimensions that its wielder desires, effectively giving it the longest reach of any sword in the world.

The sword can also be pulled apart into the tinsaiga and the Ketsumei again, if the wielder of the weapon tries hard enough, and the two can then be forced to become one again afterwards.

Because of the weapon's demonic origins, it seems to have a particular affinity for Hell and its denizens, granting them much stronger versions of its powers. Chrono himself was able to flood a small island in flames, and Avarice claimed to be able to freeze an entire planet solid. Despite this, the weapon will warm up to its owner eventually, and slowly grant them access to more of its power the more it is "fed" with the souls of the living and the blood of the deceased.

Additionally, the new sword's "inner word" is a barren desert of white sands rather than a frozen tundra.

Interestingly enough, Izoki Ross seemed to be able to use lightning magic and conjure storms with the use of the newly-forged Kurikara.

Sentience
The sword seems to exhibit some amount of sentience, as it actively chooses favourites among the many who have wielded it, and will occasionally respond to words, sentences, and actions with bright flashes of light and other effects. Chrono also claimed a couple of times that it was a living being, and that it had a spirit and a face. If this is true, it refuses to show itself at all, to anyone.

Colour Affinity
The Kurikara seems to force spells cast through it to take on a particular colour. Flames shot through the sword will always burn blue, ice and frost shot through the sword will always freeze cyan, and Izoki's lightning attacks always appeared bright, burning red. It is unknown as to why the blade does this; it simply does.