Kenjaku has been imprisoning sorcerer Gojo Satoru in the Prison Realm since since Chapter 90 of the Jujutsu Kaisen manga. By taking over Geto Suguru's corpse and trapping the stunned Gojo inside the impenetrable realm, the old evil shaman manages to catch the strongest off guard.
Jujutsu High students must enlist the aid of Hana Kurusu, dubbed the Angel, whose cursed technique extinguishes all others, even the Prison Realm, if they are to succeed in freeing their professor. The cost of the angel's assistance seems to be Itadori's life. However, Yuta Okkotsu's cursed method might be able to release Gojo and so save Itadori Yuji.
What Is Jujutsu Kaisen's Cursed Technique by Yuta Okkotsu?
Yuta Okkotsu first appeared in Jujutsu Kaisen 0 as a meek and frightened boy afraid of his power, but quickly grew to be a sorcerer capable of taking on some of the most challenging curses and cursed energy users alike -- including Geto Suguru. Yuta is one of four special-grade sorcerers and, in Chapter 173, was declared the second-strongest Jujutsu Sorcerer behind only Gojo, so it's clear his power is off the scales. While fans have been aware of the Jujutsu High student's innate talent for a while, the specifics of his technique have only recently been revealed.
In Chapter 178 of the manga, an intense match between Yuta, Ryu and Tatako revealed the young sorcerer's technique. Fans saw a glimpse of it in JJK0 when he successfully mimicked Inumaki's cursed speech. Yuta's cursed technique is Rika, who remained with him after the death of Rika Orimoto. While they are connected through Yuta's ring, he benefits from a cursed energy supply, cursed technique use, and Rika's complete manifestation -- though this only lasts for five minutes. With Rika as his cursed technique, Yuta can essentially copy other cursed energy users' techniques, as he did with Inumaki and, more recently, the ancient sorcerer Dhruv.
What Yuta Could Do To Aid Itadori, Fushiguro, And Save Gojo
Itadori and Fushiguro entered the Culling Game to find Hana Kurusu who, according to Master Tengen, has a cursed technique able to eliminate any other. This includes the ability to open the back gate of the Prison Realm, which Tengen has in his possession. The duo decided the Angel's help is necessary to free their mentor, as the other means of escape -- the Inverted Spear of Heaven and Black Rope -- were destroyed by Gojo himself. While the girl is willing to help, she has terms that must be met. Kurusu wants Itadori and Fushiguro to eliminate the "Disgraced One", who Sukuna quickly reveals is himself. This is a problem for the pair; Itadori would be willing to sacrifice himself to save Gojo, but Fushiguro will likely oppose his friend's decision.
However, with the reveal of Yuta's cursed technique, this fate could be avoided. If the special-grade sorcerer can copy techniques after seeing them in action, it's possible that he could meet the Angel and watch their technique, copying it to be used at a later date. Seeing as the back gate is also in possession of someone who can be assumed to be on Gojo's and the teens' side, the trio would only have to bring Yuta to the gate and Gojo would be free from the Prison Realm. This course of action would mean Itadori's life as Sukuna's vessel would not have to be sacrificed, and Gojo would no longer be trapped -- this would essentially be the easiest and most practical route.
While the extent of Yuta's copy remains relatively unknown, at this point he has been shown adopting a fair few sorcerers' techniques. Yuta Okkotsu could be Jujutsu Kaisen's key to saving both Yuji Itadori and Gojo Satoru, an incredible feat for such a young sorcerer.