Hmmm, 'reiatsu on a level you have never fathomed'. That is epic AND expected. I also think this is part of the reason the Zero Squad is so strong and it also points to the fact that the 12th Division has always been an 'R & D' department of the Gotei 13.
Overpowering mode=ON for those who've gone to the King's Palace.
Nimaiya Ouetsu. The short man behind the legend of Zanpaktou. This is rather curious. I bet he know all there is to know about Zanpaktou, and possibly how to maximise its potential in battle.
I don't think Renji and Ichigo will have it easy there. I think this will be their hardest training ever. I'm wondering, will Rukia learn the full potential of her Zanpaktou? And of course Byakuya, will he stop being a Captain after his incredible defeat, or will he fight to regain some pride and honor? I'm betting on the latter. I think he'll emerge from this a rather scary person.
I smell secrets will be revealed, and I think Nimaiya will train them in some obscure way. I'm also anxious to know how Unohana and Zaraki will train. Will Yachiru also train to fight? Curious I say, curious.
Kirio did state that everyone in the Zero Division created something significant for them to be recognized by the Spirit King and into his palace. Urahara Kisuke created the Hyougoku, or was it Aizen first? In anycase I think that is an invention that should warrant a promotion or something similar or is there more going on behind that particular story?
Anyways comments are always welcome, just keep them snowflake clean :)