Why didn't Urahara use his Bankai against Aizen in the Fake Karakura Town Arc? Why was the fight against Askin the perfect opportunity? Let me know your thoughts down in the comments - thanks everyone!

Urahara used his real Bankai: Kurosaki Ichigo

I like how both of Soul Society's lead scientists didn't bother with obtaining Bankai through training. Both came up with their own way to go around the intended way.

Can't wait to see it animated. Fingers crossed the long wait will be well worth it

Using his Bankai against Aizen would amount to him getting into a pissing match with the Hogyoku.

Thought: the stitches in the panel are where Urahara used his bankai to "restructure" space the way a plastic surgeon "lifts" a face.
Thought: Urahara was making a change to Askin's arm, and Askin left range while Benehime was still "stitching up" causing the "incision" to eventually wear off.
Thought: Aizen's shikai made it so Urahara knew he wouldn't be able to tell what Benehime was cutting apart or stitching together.

My theory is he didnt want to risk an empowered, hogyoku enhanced Aizen breaking it. It doesn't seem like the doll can move much which leaves it wide open to attacks.

It's going to be a real banger when they animate this.... goddamn.

My interpretation was that when the Bankai is disengaged, everything modified was going back to how it was, including the "fixed" injuries, basically being temporary patches and enhancements, and the eyes coming back would then just be from Orihime rejecting the damage. Urahara isn't Yamamoto, he would have her heal it (or she just would, it's Orihime) and not consider it like Yamamoto did to not ask her to bring his arm back.

The truth is that Urahara didn't have enough reiatsu to make his Bankai work on Aizen.

Theres a good chance Aizen could have ignored or broke the Bankai.

Bleach has shown that if someone has enough spiritual pressure, they can negate attacks.

For example:

1. Aizen ignores Soi Fon's "instant kill" ability because her reiatsu is too weak compared to him.

2. Ichigo uses his bare hands to break Hado 90 Black coffin.

3. Yamamoto's Bankai Sunfire armor just laughs at incoming attacks from Yhwach.

4. Ichigo Breaks Yhwach's Sankt Zwinger "impenetrable" defense with getsuga Jujisho

5. Ichigo literally flexes his muscles and breaks Yhwach's absorbing ability.

If you are high tier enough, you can just use raw energy to break someone's abilities through brute force.

I think why urahara said his bankai wasn't suited for training is the fact that the effort to output wasn't worth it. Imagine Chad is at level 10 in power, benehime will temporarily buff him to level 20, afterwards, Chad will be injured and return to level with no growth. If misuse were to use it for himself for Chad to train, then you could literally have any other combatant fulfill that positions

makes you wonder what kind of "restructuring" he's attempted on all of those mod souls he created.
maybe this character has significantly deeper and sinister implications when we look at his power and then what he's been doing for over 100 years.
maybe he's just not that much different than Mayuri...

Ahh good ol' Kisuke "gaslight" Urahara am I right

For why he wouldn’t train with people, I wonder if he keeps his bankai secret in general so that he isn’t pressured to modify other people. In any particularly dangerous situation, someone like Yamamoto or Kyoraku could say hey, modify me, Ichigo, or other shinigami until they are strong enough to stop the enemy, even though doing so would guarantee the modified people died afterwards.

Interestingly, I think if Mayuri had this bankai, he wouldn’t hesitate to use it on allies and not tell them the risk.

i always thought the stitches coming off/behind Urahara when he rushes/slashes at Askin were from his bankai speeding him up or shortening the space between then, essentially warping him forward or making the distance shorter to surprise Askin with a quicker attack

Kinda gives a motivation for him to want to breach the separation between Hollows and Shinigami as well besides healing the Vizards, as the effects of Ressurrections can be permanent so he might have figures that if his Bankai worked as one he could make it so

I like the idea that his shikai allows him to 'restructure' it's blood-mist spirtual energy, varying the energy wavelengths like Kidou does in order to use it for a vast variety of effects.  He still needs to develop the skill and knowledge to come up with useful applications for this, like how he analyzed Yammy's 'Bala' in order to negate them with the exact reverse wavelength of energy (like how Yoruichi negated Soi Fon using 'Reverse-Demon' in their first fight).

Then his bankai allows him to 'restructure' the physical matter within a range of the stitch-like threads his puppet produces.  He still needs to have full knowledge of human anatomy and biology to restructure a person in a beneficial way.  It makes sense that Urahara would need to develop his skills and knowledge to make the most effective use of his zanpakutou.

That it ties into the 'blood' affinity by giving it a sort of 'blood-price' to use is very interesting to me in how it seems opposite to Unohana's bankai using it's 'blood' affinity to provide self-healing.  As Unohana was a battle-lover who wanted to enjoy the thrill of battle, this may be taken as an indicator of Urahara's lack of a love for battle and his hard pragmatism to achieve victory 'no matter the cost'.

Maybe Kisuke Urahara saw what happened to Momo when Aizen reverse UNO carded the Captains with Kyoka Suigetsu, and he didn't want to cause further damage with his Bankai to Momo Hinamori or any of his other comrades.

This Bankai either wins in one shot, or you die. Like Kurosutchi, he has to wait for good information to guarantee a kill.
- If used on himself, the Bankai leaves him wounded.
- If used on an enemy, they can just move out of range.
- Transportation only matters if it can make a battle winning attack
Benihime seems immobile, so he could be knocked out of her area. She might also be vulnerable to attack.

Quick note on the name:

Kannonbiraki Benihime Aratame (観音開き紅姫改メ)
Translation: 'Kannonbiraki, Benihime Revised'

Kannonbiraki is a term for outward-swinging double doors, named for shrines to Kannon which feature them.
Chefs also cut meat 'kannonbiraki' style by slicing it down the middle and opening it up like double doors.

In other words, the bankai's name is basically 'Spatchcock' 😅