MAPPA had a lot of ground to cover in Jujutsu Kaisen season 3 episode 12, which crammed the Sendai Colony arc into a single episode. There was plenty of action, from Yuta defeating Kurourushi to the three-way fight between him, Uro, and Ryu. However, the studio added its own unique touch as usual.
The episode was made even more thrilling by a few adjustments, and some manga fans may have observed that certain aspects felt a little different. Every significant distinction between the two versions is broken down here.
Significant Modifications in Jujutsu Kaisen Season 3 Episode 12

An anime-original chase scene between Yuta and Kurourushi was one of MAPPA's most significant additions in Jujutsu Kaisen season 3 episode 12. In the anime, Yuta is sent on a full parkour run across buildings and beneath bridges while Kurourushi pursues him with cockroaches after the cockroach curse blocked his blade with a swarm of them.
Eventually, Yuta turns around and launches a slash that breaks up the swarm, setting up a brief but exciting fight scene. The manga didn't contain any of that. Before things became serious, it was a neat addition that allowed the fight more breathing room.
The way MAPPA handled the Yuta vs. Ryu fight was another significant shift in Jujutsu Kaisen season 3 episode 12. In the manga, Yuta closes in for a right hook after using his bare hands to deflect a Granite Blast. The anime? MAPPA gave it their all. Yuta fights one-handedly and utilizes a reinforced clothesline as a weapon in an extended sequence that takes place within a high-rise structure where entire floors are shattered. The two of them eventually find themselves in a train tunnel.
Ryu launches quick Granite Blasts, which Yuta swings away like baseballs before Ryu makes them more accurate to surprise Yuta. Ryu even unleashes a blast that fills the entire passageway. Yuta then hurls a whole train at him. It's amazing, and it is a lot.
In Jujutsu Kaisen season 3 episode 12, the three-way duel also received a significant anime-original expansion. In the manga, Yuta battles Uro while Rika battles Ryu. Everyone is simultaneously kept engaged by the animation. One of Ryu's attacks is deflected by Uro and misses. Rika is clearly enraged as Uro manipulates space to force Rika to punch Yuta.
Ryu then fires a Granite Blast that spins around him like a ring while he and Yuta go at it inside it. Before the anime returns to the events of the manga, Uro and Rika engage in separate combat before Uro executes a massive Thin Ice Breaker that targets all three of them simultaneously.

Additionally, there were several noteworthy sequence alterations. In the manga, Kurourushi slices Yuta's abdomen after the Festering Life Sword discharges something into his shoulder, causing insects to sprout from the wound. This is rearranged in the anime. Yuta and Kurourushi have extra clashes first, then both of them attack each other.
Then, a brief flashback depicts what transpired at that very moment, showing that Yuta's shoulder wound forced her to miss, which resulted in the abdominal cut. The plot is told in a more cinematic manner, yet the sequence is unmistakably different from the source material of Jujutsu Kaisen season 3 episode 12.
The scene where Yuta pins Kurourushi's severed arm was one minor but distinct alteration. He stabs it into a rock in the manga. Instead, he pins it to a neighboring bridge in the anime. Different surface, same concept.
Minor Distinctions in Jujutsu Kaisen Season 3 Episode 12

Throughout Jujutsu Kaisen season 3 episode 12, camera angles were frequently changed. The manga features Okkotsu Yuta facing the camera for a more dramatic moment when he gives the order for the civilians to flee. He is facing away in the anime. The manga shot is top-down, whereas the anime is bottom-up when he summons Rika to drop the bridge on the swarm. Little things like that occur throughout, and although they don't alter the plot, they do alter how some scenes feel.
Jujutsu Kaisen season 3 episode 12 included a number of sequences with distinctly varied character expressions. The manga gives Yuta a close-up, icy, unconcerned expression that strikes a deep chord after he kills Kurourushi. The anime loses that energy and pulls the camera back.
In the manga, Yuta is instantly shocked when Uro approaches him covertly following the battle, and his eyes widen. The camera is positioned farther back in the anime version, which is more muted. Even Ryu's moment with the cigarette felt different. The anime cuts to only the lighter and the cigarette rather than displaying his entire expression, whereas the manga lingers on his face, looking genuinely mournful.
Near the conclusion of Jujutsu Kaisen season 3 episode 12, the Thin Ice Breaker also takes a different turn. Yuta tries it once in the manga, and it succeeds. Around the five-minute connection time with Rika point in the anime, he gives it another go, but this time it doesn't work. Because of the extra attempt, Yuta is much closer to Ryu when time runs out, meaning Ryu was able to hit both Rika and Yuta. Yuta was so far away in the manga that only Rika was hit.

A minor but entertaining detail in Jujutsu Kaisen season 3 episode 12: the manga depicts Uro's left arm bouncing on the ground after Kurourushi severs it before Rika swallows it. Rika grabs it before it ever touches down in the anime. Fast and effective. She was probably very pissed about Uro making her hit Yuta.
Overall Thoughts
With Jujutsu Kaisen season 3 episode 12, MAPPA undoubtedly went above and beyond. The Yuta and Ryu train tunnel scene, in particular, is the kind of anime-only content that gives viewers a sense of exclusivity. Simultaneously, the anime sometimes softened the manga's harsher mood, colder emotions, and sharper character moments.
Each rendition is excellent in its own right. The peaceful parts of the manga are more emotionally impactful, while the action scenes in the anime are more dramatic. In any case, the Sendai Colony arc was successful.