Warning: Spoilers for Bleach: The Thousand-Year Blood War, Episodes 12 & 13It's long been obvious that Ichigo is a truly exceptional Soul Reaper in Bleach. His power stunned Rukia when they first met, and he has surprised many an enemy with unpredictable power-ups and outbursts. Now, it's finally being made clear just what makes Ichigo so special and powerful in Bleach, and it turns out to have everything to do with his parents.
Fans of Bleach have known for quite a while that Ichigo's father, Isshin Kurosaki, was once a Soul Reaper himself, and that seemed like it probably played a role in why Ichigo took to the Soul Reaper powers so quickly. However, it was revealed in this season that Ichigo's mother, Masaki, was special, too: she was one of Bleach's Quincy, like Uryu, and had some phenomenal spiritual powers of her own. But even that isn't the whole story on how Ichigo got to be who and what he is, as the most recent episodes have revealed.
In the two part mid-season finale for Bleach: The Thousand-Year Blood War, a series of extended flashbacks reveal the circumstances of how Ichigo's parents met. Isshin was fighting a dangerous, experimental Hollow when Masaki came to his rescue. Masaki lured the Hollow in and took it down, but not before it landed a significant bite on her. The bite began taking effect after a few days, and she developed a Hollow-like hole in her chest. As Ryuken Ishida, Uryu's Quincy father in Bleach, rushed Masaki to his own father for help in treating the injury, he was intercepted by a curious Isshin, and then again by Urahara, who had sensed the Hollowfication in progress. He offers them a solution: Masaki can be saved if a Soul Reaper's powers are injected into her, keeping the Hollow at bay and stabilizing her. That, of course, means Isshin would have to give up his own power, something that he quickly agreed to if it meant saving her. Isshin was given a Gigai (spare body) made with a human soul that would turn him into a Soul Reaper/Human hybrid, locking his powers away.
Ichigo is so Powerful Because He is Bleach's Ultimate Hybrid
This means that Ichigo's father was part human/part Soul Reaper at the time of his conception, and that his mother was part Quincy/part Hollow. Ichigo inherited traits from all four of these groups--Quincy powers, which are only just now manifesting; an inner Hollow, which was just revealed to form the basis of his Zanpakuto; and latent Soul Reaper abilities, which Rukia unlocked at the start of the series. Even his human genes brought something to the table, since they are what allowed him to develop his Fullbring power and ultimately restore his Soul Reaper abilities. To put it simply, Ichigo can draw from the powers of nearly every spirit race or group that's been shown in the series specifically because of the circumstances of his birth and who his parents are.
Bleach has set up Ichigo as the perfect counter to the fascistic Quincy Wandenreich by making him such a mish-mash of races. Ichigo's power may have already been incredible, but the episodes end with the promise that even what's been seen so far in the series is just a small taste of what he's capable of. Ichigo and Bleach's Soul Society are going to need every drop of power they can get if they're to defeat Yhwach and the Quincy, so it's fortunate that he has so much left to spare.
Bleach: The Thousand-Year Blood War will return with its second part in July 2023 on Hulu.