!!Per troping policy, all spoilers are unmarked. Administrivia/YouHaveBeenWarned.
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* "Wake up, Chief...I need you!" After four years, seven months, and ten days Cortana finally calls on John...
* After Cortana freaks out aboard the Infinity and outs herself as a rampant A.I., Captain Del Rio begins ordering her execution. Chief just calmly takes her back and puts her in his helmet. When Del Rio begins screaming at him to give up Cortana. What is Chief's response? "No, sir," in a voice that just screams 'I will break you if you try to hurt her.'
** To put that in perspective, Spartans are trained as perfect soldiers. Superior officers are 100% guaranteed a 'yes sir' from any Spartan. But when Cortana is threatened, for the first time in the entire franchise, we see Chief adamantly refuse to follow that order. And what's even better? None of the crew even tries to take her from him. They know Del Rio is a complete and utter {{Jerkass}}, and they won't go against humanity's hero.
* While Marines usually have witty and often humorous banter when you hang around them for a while, one of the Marines in ''Infinity's'' hanger will tell you about how in the past 4 years even when everyone though of him as KIA, he was rightfully lauded as a hero on Earth. The Marine even mentions his kids having a poster of the Chief back in their room!
* The news that Del Rio got replaced by [[ReasonableAuthorityFigure Lasky]] for leaving Chief on Requiem. Finally, we see an example of the government giving an asshole officer exactly what he deserves.
* It is a little heartwarming to know that the former Covenant races are accepted enough to be allowed to immigrate to Earth, even as some Sanghieli see it as a vector for terrorism.
* Chief refusing to consider that Cortana will fall to rampancy. he doesn't even consider it a possibility, and whenever it looks like she's slipping, no matter what the situation, Chief stops and reminds her that there is a job to do, and that he will never let anything happen to her.
* The ending has a tiny little moment where John and Lasky are looking down at the Earth from orbit. Lasky amused by John calling him sir tries to break the awkwardness of being John's superior by starting some idle chit chat, talking about the beauty of the Earth before realizing that John isn't much for small talk. He then tries to comfort him about the the loss of Cortana, only for John to mechanically reply that, as a soldier, it's his job to protect humanity regardless of the cost. Lasky finds this dismissive of John's own humanity and reminds him that he is more than a soldier, a machine, but a person. John muses on this for a moment, remembers something that Cortana told him before she died, and then goes to have his suit removed after years of constant service, being laid bare not as a soldier but as a man for the first time.
* Essentially, every moment spent with Cortana is a combination of this and TearJerker, and it culminates in Cortana finally getting to physically touch Chief before she passes on.
** "I was supposed to take care of you." "'''We''' were supposed to take care if each other... ''And we did.''" Did you ever, Cortana. Did you ever. Also doubles as a Crowning Moment of Sadness.