Type-51 plasma repeater

The Type-51 Directed Energy Rifle/Improved (T51 DER/I), more commonly known as the Plasma Repeater, is a plasma-based directed energy weapon used by the Covenant, specifically the Sangheili.

Description
The weapon's rate of fire will slow as it is fired and the weapon heats up. This can be solved by manually venting the rifle with the reload button, which can be done all at once or gradually. However, as the weapon overheats and the rate of fire slows, the accuracy of the weapon will increase due to reticule bloom.

It is very likely that the Type-51 DER/I is either new to the Covenant arsenal or its use is limited to specific branches of the Covenant Army, as it has only been encountered by the UNSC very recently and only in very limited numbers. Among its few battlefield uses was the Fall of Reach in mid-2552, in which it was used by both Sangheili and Jiralhanae. After the war, the Plasma Repeater was also used by the reformed Covenant during the Battle of Draetheus V.

Differences from the Plasma Rifle

 * Each shot of the Plasma Repeater is .5% of the battery, making a total of 200 shots possible. Each shot from the Plasma Rifle is .25%, for a total of 400 shots possible.
 * The Plasma Repeater takes 18 shots to kill a fully shielded Spartan, while only 16 are needed with the Plasma Rifle.
 * The Plasma Repeater does more damage per shot to a player's health than to their shields; the opposite is true of the Plasma Rifle.
 * The bolts fired from the Plasma Repeater travel faster than those of the Plasma Rifle (at 50.00 meters, the Repeater's shots take .5 seconds to reach the target, while the Plasma Rifle's take .6 seconds).
 * The bolts of the Plasma Repeater have a purple hue, in contrast to the blue hue of those from the Plasma Rifle.
 * The firing rate of the Plasma Repeater decreases over time; the Plasma Rifle's increases.
 * The Plasma Repeater can be manually vented, either all at once or in several intervals, while the Plasma Rifle is forced to vent excess heat all at once.
 * The Plasma Repeater features aim assist for the Elites, but the Plasma Rifle lacks this.

Trivia

 * Unlike most plasma weapons in the Halo franchise, the Plasma Repeater actually does more damage to a player's health than to a player's shields.
 * According to Bungie, the Plasma Repeater is the Covenant's equivalent to the UNSC's MA5 Series.
 * The weapon was originally designed primarily for Multiplayer for balancing purposes.
 * The Plasma Repeater actually never overheats, building up heat which slows its rate of fire and increases accuracy until it is either vented or runs out of battery. This makes it one of the few battery-operated Covenant weapons to not be burdened with a necessary cool-down.
 * There is an odd event that can be performed on the Plasma Repeater. In a Custom Game, Firefight or Forge, set Infinite Ammo to "Bottomless Clip", so it never loses fire rate due to overheating. Get a Plasma Repeater and fire it non-stop. The reticle will bloom far beyond the center of the screen. Once the reticle blooms to a certain point, it will reset itself to the middle of the screen again, repeating the process, but faster. After enough time, the reticle will simply be stuck in the center. Ceasing fire will cause the reticle to follow these steps in reverse. Not overheating gives the weapon one of the fastest fire rates in Halo Reach.
 * Page 333 of the Halo: Reach official guide incorrectly calls the Plasma Repeater the T51 DER/1 rather than the T51 DER/I.

List of appearances

 * Halo: Reach
 * Halo: Spartan Assault