Unlimited Blade Works

Sōgon'na Fōji is a high-class thaumaturgy that embodies the caster's internal world and imprints it upon the world as a bounded field. It serves as the embodiment of their soul, the result of "Sword" being both their Origin and their Elemental Affinity, and the basis of their chakra and memory-based perception skills. In general it is a pocket dimension accessible through a series of verbal incarnations whilst channelling chakra to a seal called the Jigen Gēto (次元ゲート, Dimensional Gate). Koyoichi's is located on his chest.

The Incarnation
I am the Bone of my Sword

Steel is my Body and Fire is my Blood.

I have created over a Thousand Blades,

Unknown to Death,

Nor known to Life.

Have withstood Pain to create many Weapons

Yet those Hands will never hold Anything.

So, as I Pray--

Sōgon'na Fōji!

Once the incantations have been completed, an illusionary fire that doesn't emit any heat spreads out to form a boundary and wall for the bounded field, indicating the technique was a success. The bright light fills the vision of those present, and manifests an open, barren desert, littered with countless swords anchored in the ground like grave markers in a wasteyard through absorbing all present within a 20m radius into the seal, Koyoichi included; the only opportunity to evade this technique is to get at least 21m away whilst he completes his incarnation. Monolithic black gears gyrate in the distance. Koyoichi's version has a thick haze formed from embers and wisps of black smog produced by iron forging rising from the ground to opaque the view. Its purpose is a steel manufacturing factory that produces the countless weapons and defensive armaments that extend into the horizon of the kingdom of rubble. It contains all of the raw materials needed for the formation of the weapons, and it records and analyzes all weapons and defensive armaments encountered. The number of unique weapons encountered and recorded by Koyoichi exceeds numerous thousands, although he's only ever seen utilizing his few favourites.

Swords, spears, and halberds are favored, but shields and defensive armaments are also replicable at two or three times the chakra cost. Due to Koyoichi's origin being "Sword" of which serves as the symbol of his character, all information stored is limited to close combat weapons. Weapons seen and analyzed are immediately stored within the pocket dimension for later use, enabling them to be summoned immediately afterward. The analysis of weapons is limited only to the direct use of human senses, meaning that blueprints and materials will be unable to provide the necessary information for a proper analysis. The quality of projected weapons will always be degraded by one rank due to humans being unable to fully conceptualize the existence of an object through only one sense, and they will never equal the originals.

While projecting outside of the pocket dimension, the projections are produced within Sōgon'na Fōji and then brought into the physical world. This greatly lowers the cost of reproducing them and allows for numerous weapons to be prepared at once to be summoned. Weapons can be summoned directly to the user's hands specifically through the utilization of Summoning: Lightning Blade Creation. The weapons reproduced once the pocket dimension is first activated will consume chakra, adding it to the cost of maintaining the bounded field. Additionally Koyoichi is freely able to manipulate the blades, as to levitate numerous quantities into the air and launch them as projectiles, proving effective due to the thousands present.

As the world exists within a pocket dimension, the only way to escape it once inside is for Koyoichi to end the technique at will by channelling chakra into the Jigen Gēto seal on his chest, or for him to be inflicted enough damage to break concentration and warp all inside in order for himself to steadily recuperate.