Plasma

Plasma is the fourth state of matter and is a very common form of ammunition for the Covenant. It can burn through a Marine's ballistic armor and is equally lethal to certain Covenant counterparts. Superheated plasma is found on many of Covenant weapons, including Plasma Rifles, Plasma Pistols, Energy Swords and many others. This ammo type can be found in vehicles, mainly Ghosts, Spectres, Banshees, Wraiths, and many warships. They are used in turrets, as well. Plasma Turrets, Shades, and Plasma Cannons are just some of the heavy artillery emplacements using plasma. Humans use plasma as a form of energy source and to cut heavy metals in factories but as yet they do not have the ability to use plasma as a weapon.

Starship Weaponry

 * Plasma Torpedo
 * Plasma Turret
 * Plasma Charge

Vehicles

 * Scarab
 * Seraph
 * Banshee
 * Wraith
 * Spectre
 * Phantom
 * Ghost

Weapons

 * Automated Plasma Cannon
 * Plasma Mortar
 * Twin Plasma Cannons

Explosives

 * Plasma Grenade

Firearms

 * Energy Sword
 * Plasma Rifle
 * Plasma Pistol

Turrets

 * Shade


 * Plasma Cannon

Trivia

 * Plasma weapons likely work with a high temperature pilot flame and a high power electro magnet, stripping the plasma out of the flame, and projecting it forward. This trades off the extra damage of fire for the added range and lack of dependence, on an atmosphere.
 * For gameplay reasons, plasma is less lethal to unshielded NPCs in the Halo games than in the novels. In the games, marines can take a barrage from a plasma weapon without being incapacitated, but in the books there are several incidences of plasma easily burning through both armor and flesh.
 * The color of plasma in any Halo game seems to describe the power of the gun. For example the Plasma Pistol shoots out green plasma but the weapon is not very powerful, while the forward turret on a Phantom in Halo 3 shoots out purple plasma which is very powerful.
 * In the books, it says that plasma torpedoes could rip through the armor of a UNSC ship with one hit. In Halo: Combat Evolved, however, the UNSC Pillar of Autumn managed to take several hits and remain reasonably intact.
 * The color of the plasma varies in different sets of weapons, the most notable of change differences are the Plasma Rifle's color and the Plasma Pistol's color, both of which are blue and green in respective tints.
 * There is a secret weapon in Halo 2, called the Scarab Gun. Its appearance is similar to  a Plasma Rifle but it is green instead of blue and much more powerful.

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