Armor Ability

Armor Abilities are exclusive gameplay enhancements featured in Halo: Reach. It is a refined version of Halo 3's Equipment feature, where instead of being used once, each ability will be reusable, with a cooldown time between uses. These can be accessed through each "Weapon Set" before a match is starting or during your respawn time.

Active Camo
The Active Camo provides players the ability to have Active Camouflage for a period of time, similar to Thel 'Vadam's active camo from Halo 2. The Camo depletes faster if you run, so crouching and slowly walking will deplete the Camo slower. Also, when the player moves faster, the Camo will not entirely camouflage the player, but when moving slowly or immobile, the Camo will cover the player completely. It also serves as a Radar Jammer. However, this not only jams other players' radars but the player's one as well. When the player uses the Camo, all sound is heavily muffled, so it easy to not notice a grenade or an opponent shooting.

Armor Lock
Armor Lock is a Spartan-exclusive ability that provides the player a small shield which protects the user from any harm, acting similar to Halo 3's Invincibility, and sends out an EMP blast to nearby enemies, pushing them away from the player before emerging. Any Plasma Grenades sticking to the user is de-stuck upon activation. This can allow the player to sustain any amount of damage and allows them to drop out of the map without dieing, this is common on the levels: Ravange, Pipe, Storm and the new Blackout.

This ability also varies with how long the button is pressed: the longer the button is held, the farther the final blast radius will be. This ability not only works against other players, but also at incoming vehicles.

Evade
Evade is a Sangheili-exclusive ability that allows the player to roll in any direction to avoid danger, breaking enemy lock-ons and tracking in the process.This also makes a 'copy' of where you were before you used the ability, enabling you to escape any incoming grenades and retern fire.

Jet Pack
The Jet Pack ability allows players (regardless of their multiplayer biped) to maneuver in mid-air, with the use of Jet Pack propulsion equipment (UNSC) or an Antigravity Pack (Covenant). The ability varies with the button presses. If the button is held without releasing, it will deplete continuously, but the player can also use it in bursts which deplete it less than a sustained flight. It is useful for evading splatters, grenades, and navigating maps.

The Jet Pack ability is rendered useless to players when transporting objects such as Flags and Skulls. If players attempt to use it, the object simply drops out of their hands. Fall still applies to Jet Pack users should they fall from the air. it is possible to get 'out of the map' by using the jetpack, this enables you to be immune to all damage, although bungie said yesterday that they were fixing this glitch.

Sprint
Sprint is a Spartan-exclusive ability that allows the player to lower their weapon and move at an increased speed for a certain length of time. Even though the player lowers their weapon, the player can still use grenades while sprinting. Can at times make you run so fast that you will die if you hit a wall.

Trivia

 * Armor Abilities function similarly to the Arbiter's Active Camouflage from Halo 2 and the flashlight in Halo: Combat Evolved.Can also be activated by 'shaking' the controller.