Other than him taking out the grand fisher then making a reappearance to smack Aizen around a bit do we EVER learn more about him? I mean its kinda unfair to introduce a charact er that big (big as in Ichigo's dad who for 6 or so seasons we thought was just an oddball paraent) that sso powerful he could smack the likes of Aizen around with one finger.
Not really fair you get a character like that but then never go into more detail about hishistory.. like why hes so strong... how he became a soul reaper, why the current captains (especially yamamoto) dont know how... would that mean hes been around been longer than Yamamoto and thus older than he is? etc etc. The Vizoreds got a whole 6 episode arc explaining their origins they could at least give us 1 episode to give us details about Isshin.... sooo do we even find out more eventually? Or will that remain one huge plot thread left unsolved? (btw i dont watch teh subs or read the manga so I would prefer to know if any of those questiosn are answsered without spoiling it.. I just dont wanna waste my time hoping/waiting for something thats never gonna happen)