Ichigo crossed his two zanpakutos in an X shape. Slowly exhaling he tensed his body and strained his zanpakutos together.
Almost in a whisper Ichigo spoke, "Bankai!"
His signature black and red reiatsu formed a cocoon around him. Slowly his black and red reiatsu turned into a dark blue, almost black, color. The pressure he was giving off was slowly increasing until it was at the point where Aizen and the captains thought it was impossible to move, to breathe.
"What is this power! What are you Kurosaki Ichigo!" Aizen screamed in anger and horror.
The amount of power that was coming out of Ichigo was so immense it was destroying everything it was coming in contact with. The trees, grass, the very earth was being ripped apart and turning into nothing. The captains off to the side were on their knees with how much reiatsu was coming off of Ichigo.
"This is insane!" Shunsui and Jushiro yelled in unison.
"My body is burning up!" Yelled Soi Feng.
"Sugoi! What power!" Yelled Kisuke in amazement. This was more than he could have hoped with the Hogyoku and this child was creating this pressure.
Slowly the power subsided and the captains and Aizen could see Ichigo, or what they suspected to be Ichigo.
He now had flowing black hair reaching to his waist, deep blue eyes and was covered from the bridge of his nose down to his toes in bandages. Except for his left arm which was wrapped in chains connecting to a sword, or what seemed to be one. Within his left arm was mass of black reiatsu shaped into the form of sword.
Ichigo's eyes were focused on one thing, Aizen.
Ichigo walking toward the 'scared as shit Aizen' spoke in a raspy voice, "This power is so sad, all it does is destroy."
Ichigo stopped two feet from Aizen's horrified and shaking body.
Ichigo spoke with voice that almost sounded sad, "All this power does is destroy, like watching memories pass and feeling the wind vanish. It all happens in an instant."
That's when Aizen spoke in a shaky voice, "Y-You can't! The Soul king must die! He must be killed!"
The captains were so surprised that Aizen had said something like this. They thought he was a kind man, not a traitor!
Ichigo stopped and stared into Aizen's eyes speaking, "You got the short stick Aizen. You had me to face off with and I cannot let you live."
Slowly raising his mass of black reiatsu, Ichigo whispered . . .
"Mugetsu."