Chrysalis aizen takes this. The guy's reiatsu is already on a whole new level. The guy disintgrated part of gin's arm without touching it as there aren't even finger marks on it And here comes the catch he appearantly still had his reiatsu lowered so that humans could feel it.
And not to mention gin reiatsu actually affected ichigo slightly.
Honestly and if you by chance don't believe chrysalis aizen wins imagine how powerfull monster aizen actually is, It's implied that seraph aizen is on a entire different level then his previous 2 transfromations, then monster aizen was actually able to damage ichigo which is something his seraph form couldn't do.
Not to mention aizen has ks and immortality as well.
Butterflaizen and beyond that were probably too much, anyway.
Why would we think that the captain commander would be able to feel the power of cocoon aizen? I would argue that the moment in which ishin failed to be able to perceive his power was the moment any other shinigami would have been in the same situation. I don't think its an issue of quantity of reiatsu.
As I think Aizen wins in any of his "advanced" forms. I will discuss the match of yama VS aizen without hogyoku:
In terms of strength/speed/physical prowess: here there's more proof favouring aizen in this topic, than favouring yama. But I would asume they are similar since both has shown incredible things clearly out of the level of anybody else, like tearing apart an arrancar with a punch (yama), or cutting komamura's bankai in half with a single blow (aizen).
In terms of reiatsu, they are similar too. Even if Yama is portrayed as having a huge unmatched reiatsu, I think the manga has shown Aizen has an insane amount of reiatsu too. Just remember how he lowered grimmjow to his knees or how powerful was his bakudo when he stopped Tessai's hado being just lieutenant.
In terms of intelligence, however, and for obvious reasons, Aizen is unmatched by everyone except Urahara.
In terms of zanpaktoh. Some of you have said Yama has the most powerful zanpaktoh which would make him unstopable on the battleground. Well, we all have seen how Aizen's cunning defeated Yama's allmighty zanpaktoh. But comparing just the two zanpaktohs, kyoka suigetsu appears to me as the most overpowered sword on Bleach. Remember all the problems that sword gave and not even the bankai was shown!
So, based on what I have said, I think they would be a difficult match for both, and Aizen would probably win. Farewell, Yamamoto Genryusai.
Aizen, easily. He's so powerful that it took dumbed up Aizen to lose to Ichigo. He's the most powerful Bleach character ever.
^it depends on the translation actually. A couple do outright say RJ would outright overpower aizen however there are other translations from reliable sources which say that as a probability more than anything. As in aizen being overpowered would be a likely scenario in a straight confrontation. However '"ikely" is not quite the same as certain. It also makes sense with how kubo likes to keep stuff ambiguous. More so, aizen himself fights with tricks and his zampakuto is ideal to avoid direct combat so the situation is not quite as simple as being overpowered implying defeat. Even if aizen fights yamamoto's bankai his illusion will allow him to keep as much distance as he needs and we have no clue of what aizen's bankai does just yet.
1. Yama uses RJ to attack.
2. Aizen uses illusions to dodge.
3. Aizen attacks Yama.
4. Yama surrounds himself with RJ thus causing Aizen to defer the attack.
So this would continue in one big circle until one of them makes a mistake. So I 'd say Yama vs Aizen in shikai would be based on luck more than anything else.
No, Aizen would lose. Yama doesn't need to rely on his senses to fight Aizen. Aizen was caught by his pride. Yama understood that about Aizen. To Aizen, Yama was the prize, worthy of finishing with his own blade even after WW had self destructed. Aizen is a baby compared to Yama. Theres little he could do to escape him. Even without Ryujin Jakka Yama knows patience is whats needed. When Aizen made his move Yama had him. He used the sense of reitsu which he recognized from his sword to realize that the Aizen stabbing him wasn't an illusion. Aizen has to cut you down if it's one on one. His strategy in the manga could be done again.
If it were that easy then why would Yama risk blowing up everyone? He had Aizen caught but still activated Enetsu Jigoku.
Sure Yama had Aizen caught but that more due to PIS on Aizen's part for not trying to chop off Yama's head. Same thing happened with Shinji. When he fought Aizen he should have just went for his head rather than just wasting time cutting his shoulder. Yama could only tell if Aizen was real or not after he had been cut and not before so if Aizen just went for his head he probably would have won.
So in the ideal scenario the battle would play out like this:
1. Aizen creates an illusion and goes for Yama's head.
2. Yama, seeing this possibility in advance, surrounds his head with flames so it can't be attacked. He then surrounds the rest of his body with flames as well.
3. Yama attacks Aizen but finds out he hit an illusion.
4. Aizen keeps creating illusions and avoids direct battle.
KS and RJJ pretty much render each other obsolete.
And Yama was caught in his pride as well. He himself destroyed WW without considering the consequences as Aizen himself said.
---------- Post added at 06:03 PM ---------- Previous post was at 05:26 PM ----------
As for the databook UNMASKED, here's the translated transcript:
So yeah basically the databook didn't say anything new and pretty much regurgitated everything said in the manga. It didn't say anything like Aizen's hogyouku evolutions made him weaker. No idea where you got that. His Hogyouku evolutions only made him stronger each time. But if there's one thing the databook made clear it's that Aizen knew what he was talking about and wasn't insane or out of his mind like some people said he was.