Board Thread:General Discussion/@comment-25360536-20140920031731/@comment-26134850-20150226064447

AvatarReiko wrote: Saru Wukong wrote: Ichigo's Bankai isn't broken. He was never given an Asauchi to imprint on so he hasn't been using a real Zanpakuto. He's basically been wielding his own power without a blade. The "new" Zangetsu is his Zanpakuto's true form now that he's acknowledged both parts of his soul and imprinted them onto an Asauchi.

So why doesn't he have a sealed form like everyone else.

I have 2 theories and honestly they're just that so feel free to ignore them. The first is that all Shikai releases take a small amount of spiritual energy to perform, hence why Shinigami don't just keep them at their initial release all the time. Obviously Bankai takes immensely more power to perform hence why only captains and some vice-captains can obtain it. However Ichigo's spiritual pressure is so immense that he can maintain his Bankai for months without dispelling it (Hueco Mundo and Fake Karakura Arcs.) So my theory is that his power is so immense that keeping his Zanpakuto in it's Shikai release is just an unconsious thing for him, his power, even when he's all but defeated and on death's door, is so immense it never seals.

The other idea is it could have something to do with the way the forging of the Asauchi went. Presumably when Oetsu Nimaiya forges Asauchi into Zanpakuto's he forges them into a sealed form before they're given to new recruits. However Ichigo was there at the forging and even reached in at the final stage to pull Zangetsu forth. Nimaiya even says "It just hit me too, that right now would be perfecto. For Chan-ichi to put in a bit of his soul...and put the icing on the cake..." (the translation I'm reading might not be exact so forgive me.) This could mean that Ichigo's Zanpakuto is unique in the way it was forged and has no sealed form, it is always his Zangetsu.

But that's all just my speculation, you'd have to ask Kubo for a real answer.