Z-750 binary rifle

The Z-750 Special Application Sniper Rifle (Z-750 SASR), commonly known as the binary rifle, is a Forerunner energy channel weapon. It is often carried by Promethean Knight Lancers, Soldier Snipers, and Crawler Snipes.

Specifications
Considered to be a brutal masterpiece of Forerunner weaponcraft, the binary rifle is a weapon used by Promethean Knight units and certain types of Crawler units encountered on Requiem. Originally designed to combat the Flood at extremely long ranges, the Z-750 binary rifle is equipped with twin, core-mounted particle accelerators which fire ionized particle beams containing jacketed antimatter particles. The incredible power and accuracy of this weapon make it highly lethal, allowing it to neutralize most targets with a single shot, disintegrating the body of the target.

The weapon possesses an angular design and metallic casing. It appears to be held together, at least partly, by energy fields as indicated by its self-assembly process and floating sights. Orange highlights can be seen while the weapon is self-assembling and throughout the casing once assembly is complete; these highlights grow brighter when the weapon is fired. The sight through the scope is tinted orange and has two zoom levels, 5× and 10×. The rifle emits a highly visible orange beam from its barrel when aiming, allowing opponents to trace the user's location.

Sometime after the events on Requiem in 2558, models of the binary rifle have been encountered that fire a concentrated beam of energy, instead of just firing single shots.

Variants

 * Retina of the Mind's Eye: The Retina of the Mind's Eye, an improved model with a larger magazine capacity, contains a shackled ancilla at its core. It can be requisitioned as a Level 6 Ultra Rare REQ in Warzone.
 * Twin Jewels of Maethrillian: The Twin Jewels of Maethrillian, named in reference to the ecumene Capital, is an advanced model that incorporates dual beam emitters that enhance the weapon's anti-armor utility and increase the pulse duration, thereby decreasing maximum firing rate to just 26 RPM. Requisitionable as a Level 7 Legendary REQ in Warzone, it can also be found as a hidden weapon in the campaign missions Reunion and Guardians.

Operational history
At the height of the Forerunner-Flood war, the Z-750 Special Application Sniper Rifle was used by the Forerunner ecumene's Warrior-Servants and military constructs alike against the parasitic Flood. The binary rifle was used to eliminate emerging keyminds and particularly dangerous Flood warforms. The binary rifle became critically necessary when dealing with large Flood pure forms.

Following the firing of the Halo Array and the loss of the Forerunner's control through the Domain, many binary rifles had their security measures triggered, reducing them to formless fragments. Those located on the Promethean shield world of Requiem had their own master keys and remained intact, wielded by Promethean Knights that guarded the Ur-Didact's Cryptum at the behest of the Librarian. However, in 2557, with the Didact's release, the Prometheans under his command once again utilized the binary rifles to eradicate humans of the Unified Earth Government. However, with the Didact's apparent defeat shortly after, the Prometheans and their weapons entered the service of the Didact's ally, Jul 'Mdama and his Covenant. Later, once Cortana took control of the Prometheans, the binary rifles became weapons of the Created.

Advantages
The Binary Rifle is a weapon of extreme rewards and extreme penalties. Boasting more power than other sniper weapons, it is an excellent anti-personnel weapon, capable of instantly killing a fully-shielded SPARTAN-IV in a single shot placed anywhere on the body, and can take down most Covenant or Promethean infantry in a single body shot as well. On harder difficulties and against higher ranked Sangheili or Promethean Knights, it takes a few shots. The Binary Rifle is also capable of destroying most light armored vehicles with one or two direct shots, and even heavy vehicles with only a few more. In addition to this, the weapon has a much higher zoom level than its sniper weapon counterparts, allowing its operator to engage targets from extreme ranges.

Disadvantages
The line of fire created by the scope's orange laser sight can be seen by every player, thus giving away the location of the user. This can be negated by only zooming with the weapon when intending to shoot or by blocking the laser sight with nearby objects and surfaces in peripheral vision when scanning an area beyond with zoom. Additionally, the Binary Rifle has a slow rate of fire (roughly one full second between shots) and a long reload time (roughly four seconds without Dexterity), leaving the user vulnerable. It holds a low ammunition capacity of 2 rounds per magazine with a total of four magazines (five with the Ammo upgrade). When fired in scope, the Binary Rifle's aiming reticle recoils in a random direction, making it difficult for snipers to reacquire their target if they miss. When unscoped, the Binary Rifle's reticle is grossly enlarged, much like sniper rifles in other modern first-person shooter games and unlike other sniping weapons in Halo. This makes no-scoping incredibly unreliable unless fired at extremely close range. Quick-scoping is an option to combat this effect, though the user will need to unzoom from the second zoom level, which can cost precious time in close quarters combat.

Halo: Spartan Strike

 * Can pierce up to four unshielded target in line of sight except for Forerunner constructs (Crawler Snipe, Alpha Crawler, etc.).
 * Loaded with 16 rounds.
 * Can take down Promethean Commander / Brute Chieftain in two shots if aimed correctly.

Changes from Halo 4 to Halo 5: Guardians

 * Fires a short pulse of energy instead of single shots. While it retains the same level of raw power provided all hits land, it is no longer capable of killing the instant it is fired. The majority of the beam must hit the target to result in a kill.
 * This version of the Binary Rifle can be considered a spiritual successor to a Halo: Reach-exclusive weapon, the Focus Rifle.
 * When aimed at by the rifle, the target player's visor receives a bright glare to alert them.
 * Reload speed slightly shortened.
 * No longer has a spread penalty when unscoped, like the other sniping weapons.
 * The weapon now has a second melee animation.
 * Zoom levels reduced to 4× and 9×.
 * Maximum round count increased to 10 (8 reserve), 16 (12 reserve) for Retina of the Mind's Eye, and 12 (10 reserve) for Twin Jewels of Maethrillian.

Production notes

 * An early concept for the Binary Rifle was later repurposed for the creation of the LightRifle.
 * The Binary Rifle was originally named the "Attach Beam" during its early development stage. Said weapon is still in the game's files; it looks like an untextured LightRifle which fires sniper rounds and has the reloading animation of the Sniper Rifle from Halo: Reach. It makes almost no sound when fired. The "Attach Beam" was merely a placeholder until the Binary Rifle was eventually finalized.

Trivia

 * In Halo 5: Guardians, the binary rifle's maximum range for the scope is 343 meters, much like the SRS99-S5 AM sniper rifle.

List of appearances

 * Halo 4
 * Terminals
 * Spartan Ops
 * Halo: Silentium
 * Halo: Escalation
 * Halo: Spartan Strike
 * Halo 5: Guardians