Battle takes place where Aizen had his final battle with ichigo. Aizen has all the powers and abilities he displayed during his fight with ichigo which are basically all the abilities he had in his transcendental form. Yamamoto has all the techniques which he has shown before including bankai.
Edit:
Well, on the subject of which transcendental form aizen has I was intentionally ambiguous on the matter. I can't really point to a link however I recall reading that the last databook said that aizen at some point started evolving however each evolution actually made him weaker. I think it said that the hollow like form was weaker than the butterfly form but I just can't confirm what exactly the facts are here. My idea with the thread was that people would have a place to discuss aizen at his strongest against the full might of yamamoto. The alternative would be to create a a thread for every form aizen had (cocoon, post cocoon, butterfly and hollowish) which seem impractical. So on the subject of which form of aizen to consider here just use whichever you believe to be the strongest one so far. I hope that makes sense to everyone.
Edit:
Well, on the subject of which transcendental form aizen has I was intentionally ambiguous on the matter. I can't really point to a link however I recall reading that the last databook said that aizen at some point started evolving however each evolution actually made him weaker. I think it said that the hollow like form was weaker than the butterfly form but I just can't confirm what exactly the facts are here. My idea with the thread was that people would have a place to discuss aizen at his strongest against the full might of yamamoto. The alternative would be to create a a thread for every form aizen had (cocoon, post cocoon, butterfly and hollowish) which seem impractical. So on the subject of which form of aizen to consider here just use whichever you believe to be the strongest one so far. I hope that makes sense to everyone.
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