Saigo no Getsuga Tenshō

is a form of Zanpakutō technique unique to Ichigo Kurosaki and Isshin Kurosaki. This technique is unique among techniques as it allows one to assume a form for a limited amount of time.

Definition
By using this technique, Ichigo becomes the itself. It is referred to as the “Final” Getsuga Tenshō because if Ichigo uses it, he loses all of his Shinigami powers. For the duration of the ability, Ichigo’s hair turns black, and becomes waist-length. Light bluish-gray bandages form around his body, tightly wrapped around his torso, right arm, and face, ending just beneath his eyes. Black flame-like markings spread across his chest and wrap around his left arm, and the remains of a tattered black cloak cover his lower body. In this form, Ichigo’s body constantly emits smoky black reiatsu, most of which is focused around his right arm. Being in this form allows Ichigo to use Mugetsu. Once it is used, the transformation dissipates, in which he will then lose consciousness accompanied by intense pain with the loss of his Shinigami powers following. Then, any remaining reiatsu stabilizes and he will awaken (sometime later, roughly a month) followed shortly by the loss of his remaining Reiryoku. However, when Ichigo lost his reiatsu, a tiny portion of it accumulated in a single location inside of him over time, and he began to regain it slightly after a year and a half.


 * Ichigo generates a blade of deep black spiritual energy in his hand and swings it towards the target. Doing so causes a massive veil of black spiritual energy to erupt upwards and approach the target, darkening the sky, and heavily damaging anything caught within the blast. The energy then continues to rise, dissipating into the sky.