User blog comment:The dark lord of fire/bleach/@comment-44061-20120217005025

Yes is it decidedly Yamamoto. As far as Shinigami goes he is oldest at over 2000+ yrs, he has been captain commander for 1000 yrs, he is the strongest shinigami born in a 1000 yrs. His zanpakuto is the oldest and most powerful fire type zanpakuto and had the greatest attack power of any zanpakuto. He is master swordsman, master of kido, master of hakuda (hand-to-hand combat). This information was presented very clearly. Ichigo on the other hand is not so well rounded combat wise, he knows no kido, he know karate but not hakuda, he is a master swordsman but doesnt really know any actual techniques. He is young and impulsive. His Inner Hollow gives him a slight advantage depending on the context of how it comes out. The Visored mask was an advantage, as well as the vast amount of spiritual power he has. The downside is he doesn't know how to properly use the spiritual power and his spiritual power tends to fluctuate alot. Sometimes he can take on the bad guy and sometimes he cant. Basically his power is too inconsistent to be considered even comparable to a captain in skills, hence why there is rarely an instant of him fighting one. Aizen is a harder subject because he is considerably masterful in combat and has immense spiritual power, but his attack capability was not high, he is mostly geared toward subterfuge using his zanpakuto. Having said that the hogyoku greatly augmented his capabilities but they were in no way natural to him. He even states in the two fights, that as a shinigami without the hogyoku Urahara (via kido) and Isshin (via melee combat) would have defeated him. He then also states he couldnt withstand the attack power of Ryujin Jakka when he briefly encountered Yamamoto. Hopefully that clarifies. As far as pure Shinigami (and trumping alot of others even, be they hollow, arrancar, visored or otherwise) go its Yamamoto as number 1.