Editing Sentinel beam

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{{Era|H1|TF|H2|GOO|H3|HW|SPB}}
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{{Weapon

|image = [[Image:8311761-Full.jpg|300px]]
|name = Sentinel Beam
|manufacturer = Forerunners
|type = [[Directed Energy Weapon]]
|size = Handheld, Two-handed
|damage per hit = Chronological
|magazine = 100 battery units
|maxammo = 100 battery units
|fire = Continuous Fire
|ammotype = *Minor: Yellow-Orange Laser Beam 
*Major: Blue Energy Beam
|rate of fire = Continuous
|velocity = C, 299,792,458 metres/second.
|accuracy = Very High
|range = Infinte
|era = ''[[Halo: Combat Evolved]]'' (usable only through modding and seen by ally/opposing Sentinels), but usable on ''[[Halo 2]]'' and ''[[Halo 3]]''
|counterpart = [[Assault Rifle]], [[Plasma Rifle]], [[Spiker]]
|counterwep = [[Plasma]] weapons and explosives
|affiliation = [[Forerunner]]
}}
The '''Sentinel Beam''' is a [[Forerunner]] [[Directed Energy Weapon]]. Sentinel Beams are often integrated into the center of [[Sentinel]]s, from whom the weapon takes its name. The weapon is particularly effective against small [[Flood]] outbreaks and [[energy shields]].

== Description ==
The Sentinel Beam was designed to control small outbreaks of the [[Flood]], and was integrated into [[Sentinels]] for that very purpose. Even though the weapon is integrated into Sentinel's endostructure, it contains a secondary power source independent of the Sentinel and allows someone to salvage and use it if intact. The weapon projects a yellow-orange or blue beam of energy (reserved to the advanced [[Sentinel Majors]]), which is capable of effectively cutting through organic matter such as unarmoured hordes of Flood -- [[Infection Form]]s in particular. Continuous contact from a Sentinel Beam can be devastating against any opponent, especially in ''[[Halo 3]]''.

Like the [[Energy Sword]] and the [[Fuel Rod Gun]], the Sentinel Beam cannot be used by players in ''[[Halo: Combat Evolved]]'' without extensive use of the Dev Mode. Such usage to acquire the Sentinel Beam involves using bump possession to attain a Sentinel and then switching back to Master Chief and have him destroy said Sentinel and exchange a weapon for the Beam. The beam is not visible from the first or second person view and if the player presses the fire button a damaging red beam will appear from the center of the screen. It later became usable in ''[[Halo 2]]'' and ''Halo 3''. A more powerful blue version of the beam is only available in ''Halo 2'''s [[campaign]].

The Sentinel Beam runs on a non-rechargeable battery that runs out very quickly, yet even Sentinels created many thousands of years ago are capable of firing one. It may be possible that a Sentinel Beam attached to a Sentinel is powered by the Sentinel itself. It should be noted, though, that Sentinel Beams taken off of destroyed Sentinels often have some of the battery depleted. A possible explanation is that the Sentinel cannot power the weapon itself and relies on the battery but can recharge it outside of combat. Like the [[Covenant]]'s [[plasma]]-based arsenal, it can temporarily overheat if 20% of the battery is used up in one continuous shot; the weapon vents excess heat extremely quickly in an attempt to counter this. In addition to being effective against the Flood, the Sentinel Beam's ability to rapidly drain energy shields also makes it an effective weapon against the Sentinels themselves.

=== Monitors ===
Also worth noting is the version of the beam that the [[Monitor]] [[343 Guilty Spark]] makes use of. In ''Halo 3'', the construct uses the integrated weapon to destroy a Flood [[Combat Form]], mortally wound [[Sergeant Avery Johnson]], and fight off the [[Master Chief]] and the [[Thel 'Vadam|Arbiter]]. The beam he fires is more powerful than and twice as thick as the usual Sentinel Beam, and is bright red in color rather than orange. When a monitor is killed, no Sentinel Beam drops from it so, it's possible that this beam is not a Sentinel Beam at all.

== In the Halo games ==
In the ''Halo 2'' [[campaign]], the Sentinel Beam is a deadly weapon, easily capable of stripping the shields of an [[Elite]]. It possesses a decent rate of fire, amazing accuracy and range, and sustained attacks with the weapon inflict large amounts of damage. The beam's targeting reticule is also reasonably centered, making it easier to aim. The weapon's [[melee]] attack is about as strong as that of a [[Rocket Launcher]], and is likewise considerably slow. The melee is also capable of disintegrating a [[Combat Form]], although this process takes many hits and is impractical in most situations.

Two variants of the Sentinel Beam are seen in the campaign: the standard yellow-orange one in the silver housing, and the more powerful blue beam, which is encased in a gold housing. While the blue version is more powerful, it is also quite rare and will overheat faster than the standard version of the weapon.

The beam makes another appearance in ''Halo 3'', with a few visual upgrades and several technical fixes. Unlike its ''Halo 2'' counterpart, the weapon now has virtually infinite range and fires a much stronger beam that, if held consistently on an enemy, can destroy them within seconds. It is, obviously enough, extremely effective when used against Flood, and will cut down any form -- including the vaunted [[Pure Forms]] -- if aimed properly.

In ''Halo 3'', the weapon does not spawn on any unaltered maps, and [[gametype]]s cannot be used to force it to spawn; it is only available in [[Forge]]d map variants. This is likely due to the weapon's increased power and range, which make it devastating in Multiplayer matches.

=== Beam Variants ===
The blue Sentinel Beam used by the [[Sentinel Major]]s is a more powerful variant of the common yellow-orange Sentinel Beam, though it also overheats more quickly and its charge depletes faster. This difference is very similar to the relationship between the [[Plasma Rifle]] and the [[Brute Plasma Rifle]].

The beams used by the [[Onyx Sentinel|Sentinels]] at [[Onyx]] were a golden color, with temperatures as high as 15,000 Kelvin.<ref>'''[[Halo: Ghosts of Onyx]]''', ''page 156''</ref> Although this variation of the weapon took significantly longer to charge, it is thought to have been capable of depleting a fully shielded [[MJOLNIR Powered Assault Armor/Mark V|MJOLNIR Armor]] suit. Furthermore, Onyx Sentinels were capable of cooperating to generate golden beams capable of destroying entire [[Covenant Cruiser]]s. The power of the beams is one of many differences documented in [[Onyx Sentinel|the Sentinel variant's article]]; such differences are likely because Onyx Sentinels were guarding something even more important than the [[Halo Array]]: the [[Shield World]]s.

==Appearances==
In ''[[Halo 2]]'', it first appears on {{Levelname|The Arbiter}}, where [[Heretic Elites]] used it as a weapon to attempt to stop the Arbiter and his allies from eradicating the [[Heretic]] force, in the [[Gas Mine]]. Flood Elite Combat Forms then used it on {{Levelname|The Oracle}}, since almost all of the Elite forms were once Heretic Elites. Many of these weapons appear on {{Levelname|Sacred Icon}} and {{Levelname|Quarantine Zone}}, where the stronger blue beam versions were available from the many destroyed [[Sentinel Majors]].

In ''[[Halo 3]]'', It first appears on {{Levelname|The Ark}}, where it can be gained by picking one of the Sentinels being destroyed (by you, although they may attack you if you destroy too many, or the Covenant Loyalists) patrolling the area. Then it was seen on {{Levelname|The Covenant}}, where some Sentinels were tasked to aid the Arbiter and [[John-117]] in their escape from the Flood in [[Installation 00|the Ark]]'s [[Citadel (Forerunner)|Citadel]]. When Master Chief, the Arbiter and Johnson arrive on the new [[Installation 04B]], they had to clear the Flood blocking their way to the Control Room with the assistance of Sentinels. When one of the Sentinels is destroyed, the Sentinel Beam will remain intact. When the monitor 343 Guilty Spark was destroyed, and the Halo ring activated, Sentinels turned on the escaping Spartan and the Arbiter, which caused several casualties and left their Beam weapons collectible to them.

==Tactics==
===Campaign===
*Ironically, it is a very good weapon against Sentinels in ''Halo 2'' and ''3'', maybe because the Forerunners never planned on it being used against the Sentinels themselves.
*On the ''Halo 2'''s campaign level Quarantine Zone, provide two of your Elite allies with Sentinel Beams, and have them board the riding seats of your [[Spectre]]. Since NPCs can't run out of ammo, they make excellent weaponry. Unfortunately, further in the mission, if you manage to keep both Elites and Spectre intact to that point, you have to leave the Spectre.
*In ''Halo 3'', the Sentinel Beam performs greatly against the Flood, as Infection Forms will burst if they are even slightly touched by the beam. Human Flood combat forms will die instantly, though Elite and Brute forms may take longer to kill. Aim for the Infection Form embedded in their chest and you'll kill it. [[Pure Forms]] are tougher due to their evolved forms; [[Stalker Form|Stalkers]] and [[Ranged Form]]s will die by the time the weapon overheats whereas the [[Tank Form]]s will require two long blasts to take down from the stomach.
*In ''Halo 3'', the Sentinel Beam is very useful for taking down a [[Brute]]'s [[Power Armor]] quickly and effectively. It is also great for taking down [[Jackals]] and their shields as well as [[Grunts]]' armor, but it may overheat.

===Multiplayer===
[[Image:Sentinel Warthog.jpg|thumb|Right|A player firing the weapon from the passenger seat of a Warthog. Note the single-handed wielding.]]
The Sentinel Beam is quite rare in multiplayer games, and if available, it can be a powerful weapon in the hands of the well-trained.

====''Halo 2''====
{{Main|Halo 2}}
*This is best used in a small map like {{Levelname|Warlock}}. Also good for {{Levelname|Headlong}} as long as you have other more powerful weapons with you.
*If the Sentinel Beam is the only weapon you have, conserve ammo and rely on meleeing as much as possible. It has a quick and effective melee. Only fire the weapon when your target is far away, because ammo goes fast. Melee in close quarters, and avoid deadly crossfire. Replace it as often as possible.
*A Sentinel Beam is useful against unshielded foes, so a [[grenade]] to take down the opponent's shields followed by a burst from the Sentinel Beam can quickly kill an opponent.

====''Halo 3''====
{{Main|Halo 3}}
*During a game of [[Infection]], the Sentinel Beam is an effective way to rid yourself of chasing Zombie forces, but take care as to where you aim, since the beam is easy to spot and is likely to give your position away if the shot goes astray.
*When loading up vehicles, a Sentinel Beam in the passenger seat is an incredibly deadly tool. The most flexible location is in the back seat of a [[Mongoose]], although the passenger seat of a [[Warthog]] or [[Prowler]] is also useful and advantageous to the match. The advantage of vehicle-bound Sentinel Beams is that it can 'clothesline' foes.
*Steady shots can make the Sentinel Beam a great anti-sniper weapon. Fire at the sniper and then sweep the area. You will eventually meet your target, and they will have a difficult time evading the beam.
*The Sentinel Beam has an extremely large power consumption rate, about 5% per second, so always carry a backup weapon and try to save the Beam for emergencies.
*The Sentinel Beam was not available in any [[Matchmaking]] playlists, until it was featured on certain map variants used in the [[Bungie vs World]] playlist. Its exclusion from regular matchmaking is likely due to the weapon's power.

==Trivia==
*The [[Focus Rifle]] in ''[[Halo: Reach]]'' and [[Automated Turret]] in ''Halo 3'' shoot similar to the Sentinel Beam.
*In ''Halo 2'', there is a lone Sentinel that fires [[Needler]] rounds and drops a Needler when killed. This was meant to be a test when Bungie was experimenting with different weapons for the Sentinels. None of these new weapons made it into the final version of the game, but the lone [[Needler Sentinel]] was overlooked and not deleted from the final product. It is not to be considered canon.
*In ''Halo: Combat Evolved'', this weapon was not able to be wielded. When a [[Sentinel]] was destroyed, the weapon was either destroyed with the body, or simply too attached to be used.
*In Halo: Combat Evolved/Custom Edition, the sentinel beam is able to be wielded through hacking, though there is no HUD.
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==Sources==
<references/>

{{Forerunner2}}
[[Category:The Forerunner]]
[[Category:Held Weapons]]
[[Category:Weapons]]