User blog comment:Xilinoc/Ch. 683 - The Dark Side of Two World Ends/@comment-3286233-20160725023014/@comment-1338810-20160728074047

I definintely want to see Aizen's Bankai, along with everyone else's that we haven't seen. Or at least an epilogue databook or something that explains what all the unseen Shikai and Bankai are.

That being said, I would never stop laughing if Aizen had never bothered to achieve Bankai, because he used the illusions of his Shikai to fool everyone into thinking that he had and made up for it with sheer power.