List of items of curious thoroughness

This is a list of items placed in the Halo games that -- while not Easter eggs -- fans may find curious in that they show how thorough the artists were in designing the Halo universe.

Halo: Combat Evolved

 * Ammo messages - Many find the messages written on canisters of ammunition to be quite intriguing. The detail extends to giving Marines instructions on how to use the ammo.
 * Paranoid Marine - Placed front and center in a room on 343 Guilty Spark, this Marine intrigues people with how he acts more like a real person than a game mechanic and seems genuinely shaken by watching his friends be killed.

Halo 2

 * Hidden cigar - In the level The Armory, a cigar can be found on the floor, hidden by the trash can that hides the Thunderstorm Skull. As soon as you get off the elevator with Sergeant Avery J. Johnson, look around to the right.
 * Armory supplies - If you look at the different boxes you can find some interesting items, like Marine Boots, a mobile turret of similar design to the one Sgt. Johnson carries at the start of Cairo Station (before the "Home Field Advantage" part), and even some meals.

Halo 3

 * Screaming Miranda Keyes - To do this, first play the campaign level Crow's Nest on Normal, Heroic or Legendary. At the beginning of the level, try to obtain the Black Eye Skull. After that, begin attacking Miranda Keyes with it. She will scream in a high pitched voice. This can also be done by heading downstairs, picking up a weapon, and simply firing it at Miranda. She will not die, not even by a headshot.
 * Suicidal Marine - Halo 3 's homage to the Paranoid Marine above, this example of Ambient A.I. continues to fascinate.

Halo 3: ODST

 * Graffiti - Different types of graffiti appear in the level Mombasa Streets. Messages include: "BELIEVE" (an allusion to the Halo 3 marketing campaign tagline), "REMEMBER REACH" (an allusion to the Halo: Reach marketing campaign tagline), "YOU LOOT, I SHOOT", "KINSLER IZ A THUG", "UNSC=LIARS", "FASCISTS", "MILITIA AIN'T WORTH SPIT!", (which reference several points in Sadie's Story: the looting of banks during the Covenant invasion, Police Commissioner Kinsler's corruption, and a propaganda attempt by the UNSC), "HELL ON EARTH" (a reference to the game's overall allusion to Dante's Inferno), "TWILIGHT OF MAN" and "GLASS THIS!". On the Firefight map Windward, there is a painted face west of the spawn room. You have to jump off of the railing where the sign points off the edge. Jump off and quickly turn around.

Halo: Combat Evolved Anniversary

 * Linda-058 readouts - While Halo: Combat Evolved indicated that John-117 was the last Spartan, the Anniversary edition stays true to the updated canon of Halo: The Fall of Reach and Halo: First Strike. The game features monitors displaying scans of Linda-058's vital signs and armor readings alongside John-117's. Though John's monitors are green and covered in data, Linda's are red with all her data either absent or flatlined. This reflects the fact that at the time, Linda was clinically dead. This can be found in the room overlooking Cryo B. To see it, you must be viewing remastered graphics, not classic mode.