Armor Permutations

Armor Permutations are a feature in Halo 3, Halo 3: ODST, and Halo: Reach that lets players customize their multiplayer character's armor to their liking. In Halo 3 and Halo: Reach, this feature allows players to change the helmet, shoulders, and chest armor pieces worn by their multiplayer character. Players also have the option of choosing between being a Spartan or Elite.

SPARTAN Armor Permutations
There is a wide variety of SPARTAN-II armor permutations in Halo 3. There are eleven helmets, eight shoulder pieces, and eight chest pieces, for a total of 5,632 different SPARTAN-II armor permutation possibilities: one helmet, two shoulder pieces, and one chest piece per permutation, not including the Bungie Armor chest piece. It should be noted the Rogue, Mark V, and ODST armor have only helmet pieces, and Security Armor has both helmet and shoulder pieces but no chest permutation. The HAYABUSA Project includes the HAYABUSA and Katana permutations.

Sangheili Armor Permutations
There is a wide variety of Sangheili armor permutations, with five helmets, five shoulder pieces, and five chest pieces for a total of 625 different Sangheili armor permutations, with one helmet, two shoulder pieces, and one chest piece per permutation.

ODST Permutations
Halo 3: ODST features armor customization, though it is not as complex as Halo 3 ' s. One can play as each member of the squad having their own unique aesthetic Bungie-created armor. Players can choose primary and secondary armor colors, but the armor's main color remains the same (dark gray). Players can also choose not to wear a helmet unless they are using the Rookie character model. Choosing not to wear a helmet does not affect gameplay. Without a helmet, the player still has the same health and stamina, and they can still use VISR mode.

Characters

 * Rookie: Unlocked by default.
 * Dare: Complete the Campaign on Legendary.
 * Buck: Unlock the Tayari Plaza Achievement.
 * Dutch: Unlock the Uplift Reserve Achievement.
 * Romeo: Unlock the NMPD HQ Achievement.
 * Mickey: Unlock the Kizingo Boulevard Achievement.
 * Sergeant Johnson: Came with the pre-order of Halo 3: ODST.

The Armory (Halo: Reach Permutations)
Halo: Reach offers a new and more abundant amount of player customizations. As a new feature, the customized character will appear in Campaign mode as well as Multiplayer as Noble Six. Players will also be able to choose whether their character is male or female, which will change their body type. The Firefight Voice of the player can also be changed. There are ten available slots for armor customization in accordance with the attached picture for the section. The ten available slots customizable to Spartans feature the ordinary Helmet, Right and Left Shoulders, and Chest Pieces, returning from Halo 3. The new slots are the customization of the player's Knee Guards, Visor Color, Wrist, Armor Effects, Utility, and Firefight voice. Halo: Reach also grants players the ability to add various accessories to their armor, such as helmet cameras and bandoleers, which affect aesthetics only.

Armor Effects are effects on your character model performed while either living or dead, depending on the one chosen. Two post-mortem Armor Effects icons have been revealed.

Firefight voices include John-117, Cortana, Edward Buck, Avery Johnson, Pete Stacker, Auntie Dot, and members of Noble Team. It is currently unknown if others will be available.

By winning or finishing Matchmaking games, beating Campaign levels, playing Firefight, using Forge, getting Commendations, completing Achievements, or by completing daily and weekly challenges, players will be able to earn "credits" (cR) which will allow them to purchase new armor. Elite armor customization does not cost additional cR, but requires the player to reach a certain rank; for example, to obtain the armor of an Ultra Elite, the player must reach the rank of Warrant Officer.

Additionally, the Limited and Legendary Editions of Reach include exclusive armor permutations/effects for your player character. The Limited Edition comes with the "Sangheili Officer" Elite permutation, while the Legendary Edition includes the aforementioned permutation, along with a Spartan "Flaming Head" effect. A redeemable token that gives the player access to the Recon Helmet will be bundled with the game to all sales made on the release date, and with all pre-orders outside of the United States. However, if the player is equipped with the exclusive flaming helmet effect, the flames will be visible during gameplay but will not be shown in cinematics.

It was demonstrated in Red vs. Blue Halo: Reach PSA: Deja View that Jun-A266's ghillie suit will be usable, and that a combat knife can be placed on various places of the body.

Trivia

 * There was originally going to be an Arbiter Armor Permutation in Halo 3, but it was taken out before the game ' s release. Bungie, however, did not explain why. Many fans expected it to be released as DLC, but due to the nature of the game that would be impossible.
 * In Halo 3, the neck of an Elite (regardless what Armor Permutation used) is completely immune to any form of damage except for a shot from a charged Plasma Pistol. In addition, the projectile will simply pass through the neck, as though the neck wasn't there, without a blood spatter. This is because both Elites and Spartans share the same hitbox (where you can hit the character), but have different models.
 * Each Elite also has a modified neck, either sleek black or a different model such as scale-like plating at the back of the neck.
 * It is likely that players will be able to use the Elite character models in Halo: Reach Custom Games, as they were utilized in several gametypes that appeared in matchmaking during the Halo: Reach Multiplayer Beta. These included the Slayer gametype variants 'Covenant Slayer'; in which the players on both teams used Elite player models and Covenant themed loadouts, and 'SvE Slayer'; which pitted a team using Spartan player models and UNSC themed loadouts against another team using Elite player models and Covenant themed loadouts.
 * The armor in Halo 3 was originally planned to be more detailed, with dents and other details in the armor, but this detail was never implemented.
 * In Halo: Reach Elite models are earned rather than bought. Unlike Spartan permutations, Elite armor comes in a full set and can't be changed.