Board Thread:Questions and Answers/@comment-28648393-20160728233147/@comment-27392440-20160828190056

This is hypothetical on my part but it seems like Ichigo's real power has always been to link to the powers of others. He did it at the start of the series to take Rukia's power, even though he never showed fullbring his whole life he developed it almost as soon as he encountered the fullbringers, he was the only one of Isshin's kids to link to and take on White's power, this would explain how he pulled off that random power-up in the hell chapter movie and it would even explain how his zanpakuto power is a carbon copy of his dad's. In fact in a series where your powers represent the unique nature of your soul Ichigo has never to my knowlege shown a technique that is his alone. So it's possible that, on the off chance I'm right, even if his 2 inner spirits were taken some link to Isshin may have given enough to regerate the more shinigami-like parts of his hybrid powers only.

There's even still a chance that he has a zanpakuto spirit that was just dormant all this time, I mean if you think about it the hollow came from White and old man came from Yhwach so unless everything that makes up Ichigo comes from something external to him he has to have some part of him that represents his own soul and if hollow and quincy zangetsu powers are gone by process of elimination there may be a pure shinigami zanpakuto spirit that awoke to take up the slack, which could explain even the significance of it taking its old shikai form to an extent.