I seem to be fascinated with Ainz lately. So once again the Great Tomb gets bounced around. This time it lands just outside the Seireitei. The 13 Court Guards are of course disturbed. Ainz is worried about his survival. So they decide to slug it out. Let's say it's the time where Head Captain Yamamoto is alive and there hasn't been the slaughter of the 1000 year war, so there are lots of soul reapers. Ainz has his Floor Guards, and Death Knights.