Bleach's anime officially revives cut manga battles
An interview with Bleach creator Tite Kubo suggests that the upcoming second episode will feature fights that weren't in the original manga.

Warning: Some Spoilers for Bleach: The Thousand-Year Blood War, episodes 1-13
The long-awaited return of Bleach, an adaptation of its final arc, the Millennium Blood War, exceeded many fans' expectations, delivering beautifully animated versions of Bleach's most epic battles and characters. The anime even picked up some areas where the manga skipped scenes, but it's now teasing a whole new fight for the upcoming second batch of episodes.
Bleach returned in October for 13 episodes, ending at some dramatic point, leaving fans waiting until summer for the next installment. The addition of new scenes has been one of the highlights for manga readers as they finally gain some insight that was unfortunately hastily overlooked the first time around. In an interview on Japan's Bleach website, series creator Tite Kubo confirmed that new content will continue in the second installment, but this time it's bigger and focused on previous battles that took place off-screen.
In the interview, the interviewer asked Kubo (and Ichigo's Japanese voice actor Seiichi Morita) what part of the second game (used in Japan to refer to a part of the season) they were most looking forward to. Kubo is out Saying "the second fight has a new fight that wasn't there in the original one." Kubo described how the animation team was approached and asked if they could include a fight he was forced to cut earlier. They chose a location for the fight, and Kubo drew up a few pages of sketches showing how the combatants would move, fight, and transform, and handed them over as a guide for creating new scenes.
What Missing Bleach Fight Could This Be?

While the war between Bleach's Soul Society and Quincy is somewhat peaceful, it won't last long. With combat getting ready to restart, there are plenty of possibilities for this new animated fight. For example, Reaper's Zero Squad is supposed to be very strong, but they rarely get a chance to prove it in the comics. The midseason finale also ended with Uryu joining Bleach's Wandenreich, so there may be some cuts to the battle involving Uryu, perhaps pitting him against the Soul Reapers again. Another complicating factor is how much the second installment will adapt to the manga; in interviews, Morita seemed Surprised that the plot of the second episode served its purpose. The pace of "Thousand Year Blood War" is definitely faster than the original anime or manga, with 5-6 chapters per episode. That would bring the second batch of episodes to around chapter 610, though obviously anime original content, like this new battle, will slow the pace down a bit.
Fans had a lot of complaints about Bleach's rushed manga ending, so it's good that the anime adaptation took the opportunity to patch up some missing pieces. The only way to really learn about this new content is to wait and see.
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