Per wiki policy, Spoilers Off applies here and all spoilers are unmarked. You Have Been Warned.
"Hello World!"
- The end of the season 3 episode "Cold", where Chief notices that the Halo 3 map Cold Storage has mysteriously disappeared from Jon's Xbox. No real explanation is ever given for the map's disappearance, as all characters deny any involvement in the incident and it's never really brought up again. While it may not be as scary as the later parts of the series, it's still fairly unsettling.
- Chaos Theosis is the villainous faction of season 6, and they prove to be a legitimate threat early on. For one, they can ban you by killing you only once, even if you quit the game or turn your Xbox off. Additionally, their rampage at the end of "Remission" is just chilling and further proved just how dangerous they really were as a group.
- The season 7 episode "Heat" has Chief's accidental murder of Cortana, which drives much of the plot for the remainder of the season. What's especially chilling about it is Cortana's voice as she was melting, as Chief tries to turn off the oven in vain.
- The following episode, "Ashes", has Chief suffer an episode while playing a game of Oddball in Halo: Reach. When he gets a hold of the oddball, it has the appearance of a flaming skull; this causes Chief to have a traumatic flashback to Cortana's death that causes him to immediately stop playing.
- The opening of "Descent". It features a flash-forward depicting Chief, seemingly torn in half, lying motionless on the bathroom floor while Arbiter contemplates suicide by jumping out of the apartment window.
- After killing Cortana, Chief starts seeing hallucinatory images of her all over the place, but this becomes Nightmare Fuel for the viewers in the latest episode, "Wake", in which Chief gets angry at the controller's faulty batteries, looks back up at the screen, and a GHOSTLY IMAGE OF CORTANA IS STARING STRAIGHT AT THE CAMERA. Time to change your underwear, viewers!
- Eugene's final words after a long pause, followed by the gunshot, can be quite chilling.Eugene: So long.
- In "Ignition", Arbiter is so infuriated upon learning the truth about Cortana that he tears Chief apart into five pieces - the top piece, a limbless upper torso with Chief's visorless head, spouting gibberish endlessly in agony.
- Season 7's ending. To sum it up, Chief decides to end everything with a literal bang, and how do they do it? Burning down the entire apartment building.
- The shooting range scene in "Nervewreck", with Arbiter's vision of Eugene suddenly rushing towards the camera.
- The opening and end of "Hello, World!", which introduces a new character assimilating players by fragging them with a hack that returns them as zombie-esque drones who go on to kill/infect other players whilst repeating "Hello, world" in Machine Monotone endlessly.
- "Alt-Right Delete" reveals him to be none other than former Chaos Theosis member Adam McIntyre, having done 5 years time in juvenile hall, and later prison (due to lack of space in juvie). He's done a lot of growing up, but not the good kind. Adam's "Hello World!" hack is also shown to not only Fragban and steal account info of his victims, but to cause the affected Xbox to EXPLODE, LITERALLY fragging and KILLING the victims. Furthermore, Adam proves how dangerous he has become by killing Clyde (Who was on Adam's side during their time with Chaos Theosis, mind you), absorbing his faction, and bringing Kylie and her faction on board.
- During the events of season 8, Xbox Live has become a cesspool of gang wars - profitable gang wars. Members earn up to 5-figures at a time doing God knows what in a medium originally meant for playing video games with friends. Adam's hacks quickly bring him to a position of near absolute power and a 6 figure income.
- "Play to Win" shows these earnings are sufficient enough for Adam to regularly purchase hard drugs like cocaine and ketamine.
- As much as Adam hypes Kylie as just as important as he is to his subordinates, he goes against her firmly drawing a line at exploding Xbox power supplies running a secret kill squad in order to continue using the full extent of his hacks anyways.
- Adam's endgame as revealed in "Zero Hour." It's revealed that Adam attempts to combine Fragban 3.0 with Hello, World! to create a Cyber WMD called The Hate Machine. To explain; the two programs are combined so that whenever someone is killed with the hack, their Xbox still explodes but their avatar is taken over with a simple AI bot that will attack whatever players that are in the server, repeating the process until there are no more user-controlled players. And that's not the worse part! Then, when there's no more players, the bots will then jump to a random server across the network, repeating the process in server after server, potentially causing the deaths of thousands of innocent players.
- The confrontation between the Arbiter, Adam, and Claire in "Zero Hour". If Chief hadn't shot Adam's minion and caught Adam by surprise, Adam would've killed Claire (who was pregnant) right then and there, meaning he would've killed both a mother-to-be and her child in a rather brutal way. The most disturbing part? Even though he wouldn't have known she was pregnant, knowing how fucked up Adam is, he likely wouldn't have cared in the slightest even if he did know.
