Sentinel beam

The Sentinel Beam is a Forerunner Directed Energy weapon, and is the primary weapon of Forerunner constructs, specifically Sentinels.

Introduction
The Sentinel Beam is a Forerunner weapon, that is an integral part of Sentinels, who use it to control the massive outbreaks of the Flood. However it was designed to only fight small outbreaks. It is projected as a yellow-orange or blue beam of energy that can efficiently cut through the hordes of Flood, Infection Forms in particular, that the Sentinels have to deal with when an outbreak occurs. The blue Sentinel Beam is a stronger, more efficient version of the common yellow-orange Sentinel Beam, but it overheats more quickly and its charge depletes faster. The blue Sentinel Beam is used by Sentinel Majors.

Like the Energy Sword and Fuel Rod Gun, the Sentinel Beam is not player-usable in Halo: Combat Evolved, but it is usable in Halo 2 and Halo 3. The more powerful blue version of the beam is only available in Halo 2 campaign, not in multiplayer.

The Sentinel Beam runs on a non-rechargeable battery with a maximum charge of 100, so this means that when depleted you will have to find a new weapon or a new Sentinel Beam(this is common for many of the Covenant weapons). Like the Covenant's Plasma weapons, it can temporarily overheat if 23% of the battery is used up in one continuous stream. It is effective against the Flood and Sentinels, and is able to quickly deplete shields like Plasma weapons, though it does less physical damage.

Continuous contact from a Sentinel Beam can be devastating against any opponent, especially in Halo 3.

The beams used by the Sentinels at Onyx were a golden color, an odd exception to the usual rule of blue beams being the most powerful. Although this variation of the weapon took significantly longer to charge, it is thought to have been capable of destroying a fully shielded Spartan, and gained exponential increases in power when multiple Sentinels worked together, to the point where it could be used to destroy entire fleets of Covenant Cruisers. It may be worth noting that there were some other differences between the Sentinels of Onyx and the ones that appear on the Halo Installations; these were pointed out by Dr. Halsey. These are listed under Onyx Sentinel. Also, the Sentinels on Onyx are of a different design to the ones on the Halo rings, as these were meant to guard a Shield World, not Flood containment facilities.

In the Halo 2 campaign, the Sentinel Beam is a deadly, all-around good weapon. It possesses a decent rate of fire, amazing accuracy & range, and great damage against both shielded and unshielded opponents. The beam's targeting reticule is also reasonably centered, providing a better aim. The weapon's melee attack is about as strong as that of the Rocket Launcher's, and is likewise considerably slow. 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 also quite rare and will overheat faster than the standard beam.

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 a few 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. The beam does not spawn on any multiplayer maps using the standard weapons settings, and players cannot spawn with them in any game type, custom or otherwise. However, the weapon must (at this time) be added to a map through the Forge editor for use in multiplayer. Combat-wise, in Halo 3, this weapon is a very useful weapon in the right situation, the ammunition is depleted quickly, but it is a powerful tool in combat.

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 Arbiter. The beam he fires is more powerful, twice as thick as the usual Sentinel Beam, and is bright red in color rather than orange.

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

In Halo 3, It first appears on the Ark, where it can be gained by picking one of the Sentinels being destroyed (by you or the Covenant Loyalists) patrolling the area. Then it was seen on The Covenant, where some Sentinels were tasked to aid the Arbiter and Master Chief in their escape from the Flood in the Ark's Citadel. When the two warriors and Sergeant Johnson arrive on the new Installation 04(II), 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.

Character Compatibility

 * Elites
 * Spartans
 * Sentinels
 * Monitors
 * Flood Combat Form (Human)
 * Flood Combat Form (Elite)

Multiplayer
The sentinel weapon is quite rare in multiplayer games, and if available, it should be your weapon of choice. In Halo 2, the Sentinel Beam is useful, but in Halo 3 it is one of the best weapons in the game. On many Infection game types, when zombies have instant death, the Sentinel Beam is ridiculously powerful, allowing a player to sweep an area at any range, killing all foes in the immediate area. The Sentinel Beam is one of the few weapons that is wielded in both hands on foot, and in one hand in a vehicle besides the Mongoose(another is the Brute shot).

Halo CE

 * The Sentinel Beam is only available for use if you bump-possess a Sentinel in Custom Edition, or simply modify the desired level so that you start with a Sentinel Beam, or so that you start as a Sentinel. The beam never runs out, but it is relatively ineffective against other players. Otherwise, this weapon is not seen at all with anything other than the Sentinels in Campaign.

Halo 2

 * In Halo 2 multiplayer, the Sentinel Beam appears as a default weapon in the bases on Backwash and on Desolation, and it can be added to most maps using Forge on Halo 3.
 * The weapon can actually make it harder for enemy players to see if it is aimed at their head but should only be done at close to medium range.
 * This is best used in a small map like Warlock. Also good for 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 melee as much as possible. It has a greatly effective and quick melee. Only fire the weapon when your target is far away, because ammo goes fast. Melee in close quarters, and avoid deadly crossfire. Replace as often as possible.
 * If you have other weapons on the map, use those. The Sentinel Beam is effective, but hard to aim. Only use it if you have advantages over other players such as better aim, etc.
 * A Sentinel Beam is useful against flesh, so a grenade to take down the opponent's shields followed by a burst from the Sentinel Beam can quickly kill an opponent.
 * A widely refuted myth about this weapon is that it can score head shots. This is partially true. Like the Magnum, Battle Rifle, Covenant Carbine, Sniper Rifle, and Beam Rifle, it can get head shots, but only if you are already aiming at the head when you start shooting, i.e., it will not work if you sweep the beam to the target's head.
 * The beam is accurate at any distance.
 * Ironically it is the best weapon (except for the M90 Shotgun) for destroying sentinels.

Halo 3

 * During a game of Infection on Halo 3 Multiplayer, the Sentinel Beam is an effective way to rid yourself, of chasing Zombie forces, but take care as to where you aim, since the laser 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 is also useful and advantageous to the match. The advantage of vehicle bound Sentinel Beams are that it can clothesline foes.
 * Even though it is a headshot weapon, try aiming it at the stomach area for better accuracy, as the weapon is powerful enough to not need a headshot.
 * Steady shots can make the Sentinel Beam a great sniper weapon. Fire at a target, 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 is also very useful for taking down Brute Armor quickly.
 * The Sentinel Beam is also great for taking down Jackals and their shields as well as Grunts' armor, but it may overheat which leaves you a sitting duck for attacks against you.
 * The Sentinel Beam is great against the Flood, as Infection Forms will burst if they are even caught in the beam, Human Flood forms will die instantly, 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, but Stalkers and Ranged Forms will die by the time it overheats. Tanks; however, will take two long blasts to take down, from the stomach aim for the mouth.

Trivia

 * It is currently not available by default in any known Halo 3 map. It is available in Forge, and Custom Games, though.
 * This is the only player-controlled Forerunner Weapon seen in the Halo Trilogy.
 * The Automated Turret uses a similar beam to that of the Sentinel Major from Halo 2.
 * In Halo 2, there is a lone Sentinel that fires actual 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 not deleted from the final product.
 * In Halo 2, when a Sentinel Major's Sentinel Beam is dropped, it has the steel color of a Minor's beam, but when picked up is colored gold like a Sentinel Major's beam, denoting an error on Bungie's behalf.
 * In Halo 3, there are sparks that come off of the beam when fired.
 * The Sentinels on Onyx have beams with temperatures as high as 15,000 degrees Kelvin
 * The Sentinel Beam in Halo 3 seemed to have unlimited range.
 * Some have speculated that the Spartan Laser was based on the Sentinel Beam. This is, if unlikely, certainly possible as Humans were alleged to have discovered Forerunner structures before meeting the Covenant.
 * Despite the fact that it has no scope, the Sentinel Beam can also be treated as a sniper weapon, due to the range and accuracy.
 * A Sentinel Beam can easily drain a player's shields on multiplayer, even with overshields on. A player can be killed in just a few seconds of direct fire.
 * A concentrated beam fired from this weapon held halfway until it overheats can destroy a Mongoose.
 * The only enemies that use Sentinel Beams besides the Sentinels are Heretic Elites and their infected counterpart in Halo 2.
 * Spartans and Elites hold the sentinel beam like a Support Weapon such as a turret or a Flamethrower.
 * The Sentinel Beam is used as "cutting laser" and a holy beam to end the Preceptor's power in the popular Halo Machinima The Codex.
 * A quick shot followed by a melee will almost always kill an enemy.
 * In Halo 3, the Sentinel Beam's range is equal to the sniper rifle though not as effective at long range use.
 * The Sentinel Beam's beam appears in orange and light blue colors. 343 Guilty Spark uses a much stronger and more powerful red colored Sentinel Beam.
 * In Halo: Combat Evolved, this weapon was not wieldable. When a Sentinel was destroyed, the weapon was either destroyed with the body, or simply too attached to be removed.
 * In certain Halo: Custom Edition maps, you can use both the Minor and Major Sentinel Beams.
 * When the popular machinima Red vs Blue first began utilizing Halo 2, the players used as camera men used the Sentinel Beam to film as the makers of the show felt that it took up the least amount of room on the screen.
 * The Sentinel Beam is extremely powerful against Flood, and if the player concentrates a shot for a few seconds it will kill most Flood Forms.
 * Forerunners referred to the Sentinels and their beams as "our very basic countermeasures".
 * While your Sentinel Beam is recovering from overheating, you can throw a grenade, though there is no animation.
 * The beam from the Sentinel beam bears a resemblance to the beam that appears in the Halo 3 multiplayer map, Sandtrap that comes form the large structures( or possibly the Easter Egg) when the land mines fail to kill you. Although the Sentinel Beam's beam is larger and much more brighter.

Related Links

 * Sentinels
 * Sentinel Major