Editing Cortana (level)

*The room where [[Cortana]] is located is a remake of the room from the level ''[[High Charity (level)|High Charity]]'' from ''Halo 2''. This room is located before the final gravity lift where Cortana says "apparently these are the Prophet Hierarch's private quarters, their inner sanctum". In the "inner sanctum" there are three doors, two located opposite one another, with a third, opposite a large view screen. In the level ''High Charity'', the Chief enters through the third door, and exits through the door on his right; in the level ''Cortana'' from ''Halo 3'', he enters through the door that was locked in ''Halo 2'' (opposite the door that leads to the final gravity lift). The graphic design of the room and the rest of High Charity's interior has been remodeled in ''Halo 3''. It resembles the corridors of the {{Pattern|Ket|battlecruiser}} ''[[Truth and Reconciliation]]'' from ''Halo: Combat Evolved''.

*There is an area with a dead ODST (not the crashed Pelican). It is unknown how he made it so far from the Pelican or if he was from the Frigate {{UNSCShip|In Amber Clad}} before the Flood attacked [[High Charity]]. There is also a Flamethrower in this area which hints to a final stand since he's in a pipe area with one opening.

**In the opening cutscene, the Master Chief is shown holding the shotgun no matter what weapons the player starts with. However, if the player starts with the default loadout, they are holding the assault rifle instead of the shotgun with the shotgun as their backup weapon.

*As seen later, primarily in ''[[Halo Wars 2: Awakening the Nightmare]]'', [[High Charity]] was not completely destroyed when the player detonates its reactor. This shell is eventually covered by a [[containment shield]] under the command of [[000 Tragic Solitude]].{{Ref/Game|HW2|Detail=''[[Phoenix Logs]]'' - ''Idle Hands II''}} This is later breached by [[Voridus]] and the [[Banished]] in ''Awakening the Nightmare'', [[Outbreak on Installation 00|releasing the Flood that had survived the destruction of High Charity]] and the firing of [[Installation 08]].

*After [[Thel 'Vadam]] joins you in battle against the [[Flood]], you can find his [[Type-26 Banshee|Banshee]] outside by the [[D77H-TCI Pelican|Pelican]]. You can jump up to his Banshee and even destroy it, but it is impossible to enter the vehicle.