All of the attacks aizen took from urahara were taken while aizen was with his guard down though. Even the kido that ultimately took down aizen was dealt when aizen was not avoiding attacks. More so, as far as kido goes I don't think they are much of an option in this fight. The kidos that could prove deadly would be the 90th level ones and urahara cannot do those without an incantation. In any scenario where unohana cares to go for the kill there is no way urahara can do a high level kido. Then there those beneath the 90th level but I don't think unohana would let herself get caught easily. To be honest I don't think urahara could even hold his ground in a swordfight against unohana, the result would be basically the same as the first hundred times unohana killed kenpachi (easy, quick and painless). And then of course there is the fact that unohana does have her bankai available and urahara does not. We do not know what it does but it presumably enhances unohana's combat in some form otherwise it makes no sense for her to have used it at all against kenpachi. So even with high level kido urahara has to deal with an actual bankai.... Urahara is dangerous because he is smart, not because he is strong. He is strong but I don't think he has shown more strength than your average captain. On the other hand unohana exceeded the guy who took out quinta without any effort whatsoever.
I don't think Unohana is the kind of opponent Urahara (or for that matter current CC Shunsui) can defeat without bankai. She is possibly the best swordsperson SS has ever seen, skillful enough to defeat another captain in quick succession, a captain whose forte is also swordplay. She is the most vicious criminal in SS history, a member of the original Gotei 13 which was said to be the strongest. IMHO Unohana can end the fight pretty quickly if it comes to a swordfight, something Urahara will most likely try to avoid. Considering that Unohana can heal herself during fighting, it will be pretty hard for Urahara to finish her only using his shikai assuming that he can catch her. Kido without incantation would be impractical in such a fight and I'm not sure lesser kido would pack enough power against such a powerful opponent. On top of those Unohana can also use her bankai which tips the balance even further in her favor. If Urahara could use his bankai which was hinted to be quite powerful, things might have been different but under these circumstances I see Unohana closer to victory.
Kirinji knew of Unohana's power, thats why he said now is not the time to be healing (or a healer). Anyone who is old enough to know 200 years ago should know Unohana is not to be crossed. Shunsui and Juushiro are examples of this. Even Ichigo got that scared look from her.
Unohana can constantly heal herself so the best way to defeat her is to one shot her and in Urahara's arsenal i don't see anything which can one shot her...
So the battle will be dragged and in lengthy battles person with superior stamina always have a great advantage, between Uhohana and Urahara i guess Unohana is the one with more stamina plus her mastery over kido is above decent,
SO IMO this goes to Unohana
Kirinji taught her healing techniques, so it's only logical, that he knew about her true nature. Is it testament of her strength? NO. Is it proof, that she isn't wholehearted healer and has dark past? Yes, it is.
Last edited by Duniak; August 16, 2013 at 12:24 PM.