Okay, opening a huge can of worms here. How should the captains (and equivalent characters like Ichigo and Yoruichi) be ranked in strength in order from greatest to least? This is a very confusing subject since different captains have different strengths and will do much better or worse depending on matchups. For instance, Aizen would have easily beaten anyone until he revealed the true nature of his Shikai to everyone (why did he do that?! Worst monologing since Dr. Evil), with the exception of Tousen, who despite being one of the weaker captains could easily overcome Aizen's advantages. Urahara Kisuke and Kurosaki Isshin aren't included because we have no idea how they compare with the others. Here's my preliminary list: 1. Yamamato Genryuusai 2. Aizen Sousuke 3. Ukitake Jyuushirou (assuming good health) 4. Kyouraku Shunshui 5. Kurosaki Ichigo (yeah, this will be controversial) 6. Kuchiki Byakuya 7. Yoruichi 8. Soi Fong 9. Ichimaru Gin 10. Hitsugaya Toushirou 11. Zaraki Kenpachi 12. Komamura Saijin 13. Tousen Kaname 14. Kurotsuchi Mayuri 15. Unohana Retsu Explanations: Yamamoto is most likely the strongest in raw spiritual pressure (excepting anomalies like Kenpachi and Ichigo), plus his fire abilities could overwhelm Aizen even if hypnotized. Aizen is second due to being the main villain and having the cheapest ability ever. His easy defeats of Hitsugaya, Komamura and Ichigo shouldn't be overlooked, either. Ukitake and Kyouraku have unique double swords and seem to be the eldest of the captains; together they had a decent chance against Yamamoto, so they should be pretty high. Ichigo is surprisingly high because he is so damn overpowered! Already, the only characters that can be said with near-certainty to be better than him are Aizen (proven) and Yamamoto (I should hope so!). And Ichigo is only a powerup away from either of them. Ichigo is definitely above Byakuya, whom he outclassed for most of their battle. Ichigo only started to lose when his inexperience with his new Bankai caused him to grow weaker; he could have finished Byakuya earlier without as much trouble. The Hollow takeover showed that Ichigo has still-untapped reserves, and shouldn't be disqualified from his overall strength. Finally, at the end of the battle Ichigo's made-up-on-the-spot final attack beat Byakuya's much more artful final blow. Ichigo proved his strength quite thoroughly. Byakuya is sixth because he appears to be one of the more elite captains with his great speed and very dangerous Bankai. Byakuya > Yoruichi even though she is faster because otherwise she could have just defeated him herself and rescued Rukia right there. Byakuya > Gin as he stated very early on that Byakuya was someone even he didn't want to fight (as he dragged a protesting Kenpachi away). As above, Yoruichi < Byakuya and Soi Fong < Yoruichi by a slim margin. However, both of their power sets are the most unusual and they could arguably both be either higher than Ichigo or lower than Kenpachi. Gin seems better than Hitsugaya but not by enough that Hitsugaya isn't confident to challenge him. For a villain, Gin's strength is a little low, but he will likely get a Hollow powerup. Kenpachi is very limited by his lack of Shikai and Bankai; nevertheless, his power is terrifying and he could even challenge Aizen under the right conditions. Komamura seemed stronger than Tousen in their fight with Kenpachi. Kurotsuchi and Unohana are the weakest for obvious reasons. So to sum it up, Ukitake and Shunshui could easily be lower (but that would make Ichigo an implausible 3rd), Kenpachi could be higher, and Yoruichi and Soi Fong could be pretty much anywhere. For purely storyline reasons, Urahara and Isshin should be just above Ichigo, but there's no evidence for that. Renji might now make the list, too, but he'd be very near the bottom.