Round One Base Aizen
Round Two Monster Aizen
Setting Hueco Mundo
Aizen wins both.
Physical strikes will be useless, but Aizen's got loads of hax including kido spells. He probably also knows time-stop like Tessai.
Chances are, Aizen negates Bs powers and slaps the white off him.
Even current Aizen would own Barragan lol
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