Board Thread:General Discussion/@comment-13237238-20130724132657/@comment-4750250-20130803153258

My would be Wild Willow (野生柳, Yasei Yanagi, if Google Translate is to be believed :).

In its sealed form Yasei Yanagi most closely resembles a nodachi with an oval brown-colored tsuba and a small dark green tassel attached to the hilt.

The release command is "Drink" (飲め, nome). The nodachi is held back in a one-handed grip, angled forwards with the left arm held parallel, the off-hand held up in a challenge. Blueish green glow envelops the blade (the hilt and the tsuba stay the same) and it transforms into that of a khopesh - a sickle-like sword sharpened on the outside, rather than the inside, portion of the curve. An engraving of a willow's branch runs along the blade.

Yasei Yanagi is always hungry for spiritual energy; even when it is sealed, it requires its shinigami to eat about twice as much food as they would normally require. Consecutively, if it is released for too long without feeding it during the course of battle, it cannot help but drain the shinigami's own reserves.

There are two ways Yasei Yanagi can consume energy - either by landing a hit on their opponent, or absorbing their energy-based attack. However, the latter ability is not without its limitations - the shinigami must place themselves in the way of the enemy's attack rather than dodge it, and if their and their zanpakutō's combined power is not enough to absorb the attack completely, whatever was not absorbed will land a hit on them.

As energy is absorbed, the engraving of a willow's branch will fill up like a gauge with blueish green glow, starting from the hilt and working its way up the length of the blade. If the shinigami has been eating normally, usually they start the battle with half of the gauge already filled up. If less than one tenth of the gauge is filled up, the glow will change its color first to yellow, then through orange to red, and it is at this stage that the zanpakutō drains the reserves of its partner.

This energy can be used in two ways. First is healing oneself; I have not yet determined the correlation between the severity of the wounds healed and the amount of energy drained, some balance-oriented advise would be appreciated! :)

Second is using it to fire off kidō, skipping the incantation but retaining the spell's full might. Kidō used that way always have their energy blueish green in color, and look as if they were released from Yasei Yanagi rather than by shinigami. It is possible to both augment the kidō with Yasei Yanagi and chant the full incantation, further increasing its power. However, most likely that would give away the 'secret' behind the technique.

Yasei Yanagi would be reluctant to lend their energy to anything rather than hadō spells at first, and would require a great deal of working together as a team with the shinigami before it starts willingly giving the stored energy to heal its owner.

If broken, Yasei Yanagi would desperately try to feed upon the shinigami's spiritual energy to reconstitute itself. Given sufficient amount of food, it may thus recover quicker than other zanpakutōs, but without it, it may kill itself and its shinigami because its hunger cannot be contained.

Bankai is still a work in progress. Hope you like it! :)