From Halopedia, the Halo wiki
Replacing the Elites as the principal Covenant foe in both Halo 3 and Halo 3: ODST, the Brutes utilize a different gameplay doctrine in how they attack, forcing the player to also adapt tactics to defeat them. As the name suggests, Brute offence in the game relies on overwhelming force, utilizing the numbers of their packs in conjunction with their crude but undeniably effective firepower and their overwhelming strength in melee combat. While considerably less subtle than Elite tactics, which rely on speed, agility and tactical maneuvering, Brute tactics can still be very effective against unwary players. When at range, Brute shooting tends to be less effective than Elite shooting due to their lack of precision weaponry; however, their power in melee combat makes up for this, as they are more damaging in combat than Elites (unless the latter are armed with an energy sword). Furthermore, Brutes do display a grasp of basic tactics, having been seen in the games to utilize outflanking manuevers, as well as taking cover against shooting at least in some instances. Not to mention, it may be noted that one advantage Brutes have over their Elite counterparts is that their lack of a code of honour enables them to tactically think out-side the box, though whether the Brutes are very good at that is LARGELY debatable. The typical Brute reaction is to immediately seek the source of shots and advance towards it, either to engage in immediate combat or to then stand off at medium distance to shoot. Once engaged in combat the Brutes hunch into a more ape-like stance and begin firing upon their target(s). Often the target is subjected to a barrage of fire and explosives in excess of what Elites and Grunts can muster simply because of the rate of fire of the new Brute weaponry, favouring volume of fire over accuracy. They can often be quite tactically stupid when fighting AI marines as instead of closing in and using their superior strength, they instead shoot from mid-range which means they are fighting on the Marines' terms.
As mentioned previously, when not leading lesser Covenant forces, Brutes tend to congregate in packs of 4-6 individuals; the rank of each Brute, the number of each rank and the weaponry with which they are equipped varies with the difficulty being played. Often, these packs will consist of one Brute Captain, 1-2 Brute Majors and 2-3 Brute Minors. It can be twice that many if there is a Brute Chieftain in command nearby.
When patrolling, Brutes exhibit considerably less tactical awareness than Elites, allowing the player to often get the drop on them when the Brutes are not aware of them. In these situations, Brutes exhibit a sense of calm, confident that there is no imminent threat and some have been found testing captured Human weaponry whilst in this relaxed state, notable on the level Uprising in Halo 2.
The armour of Brutes has changed throughout the games but in all incarnations the Brutes are durable foes, able to take as much or more damage than Elites, though they are correspondingly less agile. In Halo 2 Brutes are shown to be relatively unarmoured, as their thick hides allow them to take a considerable amount of damage within the game. The Brutes' definite weak spot is the front of the skull or head; as such, targeting their heads with precision weapons such as Battle Rifles or Covenant Carbines can take down Brutes without expending the time and ammunition wasted otherwise. By the time of Halo 3 all Brutes are equipped with Jiralhanae Power Armor, giving them a boost in protection. While they are still less well armoured than Elites of similar rank this does boost their natural protection and make them harder to kill - the armour of higher ranks, such as Chieftains, sometimes exhibit characteristics such as an inability to stick plasma grenades to them. Brute armour is weaker than the Elite equivalent, and can fall apart after extreme damage, particularly plasma damage, leading the Brute to charge and attempt to get into close combat. In Halo: Reach, Brutes maintain their high durability, and can take heavy damage before being killed. Brutes have no Power Armor in Halo: Reach, with the exception of Chieftans. They wear helmets that need to be knocked off before a headshot is fatal, so good accuracy is an absolute must when facing them. All Brute ranks are equipped with the Armor Lock ability and will often use it when threatened with grenades. The lack of power armor means they are extremely vulnerable to the Needler and even more vulnerable to the Needle Rifle, as a supercombine explosion will kill them instantly. Chieftans require their shields to be depleted before they are vulnerable to the supercombine explosion. As with many other enemies in Halo: Reach, Brutes can be assassinated. However, this can be difficult to accomplish and seemingly requires that the Brute is unaware the player is behind them for the assassination to be available.
Brutes rely primarily on their own technology. They are initially found wielding Brute Plasma Rifle to deadly effect. These faster firing variants on the standard Plasma Rifle suit the Brute mentality well, allowing them to lay down a blanket of fire and keep their targets pinned down, though at he price of more rapid overheating. Higher ranking members of the pack (often Captains) are found using the Brute Shot allowing a Brute pack to lay down a withering hail of explosive fire on an enemy position. In the later months of the Great Schism, they become much better equipped, with many weapons of their own making such as Spikers and Spike Grenades (see below).
Brutes are also fond of explosives and will often use all types of Grenades in combat, although they aren't very accurate, particularly Spike and Incendiary grenades. However, on Normal and above, these can become lethal tools as they become more accurate (especially the case for Spike Grenades.) Keep in mind that the Spike Grenade acts like the Plasma Grenade, as one stick results in an instant kill. They have also been known to use Fuel Rod Cannons, Rocket Launchers, and even Frag Grenades. For some reason, Brutes seem particularly fascinated with Human Shotguns, perhaps attributable to the advent of the Mauler into the Covenant ranks. Their skill with the Covenant Carbine, makes them dangerous at mid to long ranges. On higher difficulties in the level High Charity and in the level The Covenant, Brutes will use Battle Rifles (although the latter is in a Banshee), but this is quite rare, since they regard most Human weapons as worthless (despite how effective some of these are against them).
With the onset of the Great Schism, Brute weaponry became more varied. The Type-2 Antipersonnel Fragmentation Grenade, more commonly known as the Spike Grenade, is a creation of the Brutes themselves. It is suspected that with their newly found dominance amongst the Covenant Loyalists, the Brute Plasma Rifle has been replaced with the Type-25 Carbine or Spiker. The blades that adorn this weapon are a testament to their barbaric nature and their affinity for close-quarters combat.
Brutes also have a lethal variety of close-quarters firearms. The most famous of these is the Gravity Hammer Originally only wielded by Tartarus in Halo 2, the Gravity Hammer is a favored weapon of Brute Chieftains in Halo 3. Swinging it with considerable power, Brutes use the weapon to crush their foes and knock enemies down. In game terms it is often capable of killing the player in one hit, or at least completely reducing his shields. Another is the Mauler. Analoguous to the Shotgun, the Mauler is short ranger but capable of killing a lightly armoured target in one hit, or taking the player's shields down to nil.
In Halo: Reach Brute Minors will almost always wield the Spiker or Plasma Repeater. Brute Captains will usually use the Spiker and Plasma Repeater as well, but are also seen with the Concussion Rifle, Gravity Hammer, and, more rarely, the Needle Rifle. Chieftans exclusively use heavy weapons. The Gravity Hammer, Fuel Rod Gun, Plasma Launcher, and Plasma Cannon are all available weapons for Chieftans. Though slower than Elites, they are extremely durable and can be quite smart in a cunning way. They are highly aggressive and will attempt to close distance and melee if they can.
Like the Elites, the Brutes can pilot most vehicles including Ghosts, Spectres, Banshee and Wraiths. Brutes also have the ability to Board vehicles. If given the opportunity, they will attempt to jump onto your vehicle and melee you off it. In Halo 3 Brutes use two new vehicles, the Chopper and the Prowler. Both of these are clearly Brute-built and modified with Covenant technology, signifying their newfound dominance of the Covenant military in the absence of the Elites. The Chopper exemplifies Brute tactics in vehicles - they are powerfully armed with autocannon, considerably more durable than Ghosts but slower, and lethal up close, with a ramming ability that can easily destroy most light vehicles, even other Choppers, in one hit when assisted by boosting.
A Brute Rampage (or commonly known as "Berserking") is when a Brute becomes enraged and aggressively charges its enemy in a reckless attack (in Halo 2, an enraged Brute will drop their weapon and charge immediately). The Brutes in Halo 3 keep hold of their weapon, though they still charge instead of firing it. When a Brute berserks, they may charge in a straight line towards you. Usually they will pause for a brief moment immediately before the charge, this gives you a chance to anticipate their actions. Additionally, the pause can sometimes appear to override the effects of the Tough Luck skull; in at least one instance, berserking Brutes did not jump away with this skull even when facing annihilation by a fuel rod gun. It is possible to exploit this tendency by allowing the Brutes to charge in a straight line off the edge of a cliff, while using yourself as bait. Chieftains do not drop their weapon; instead they charge with their Gravity Hammer. Captains have been seen going berserk, while wildly firing their weapon with full/semi-full power armor.
Their "rampage" stages come in two types, in Halo 2 the Brutes would run at you on all fours and then melee you to death while remaining on all fours, to escape being rammed into by a brute, all you need to do is jump to the higher ground/platform that would involve the brute to jump to you to get to you. The reason for this is that when a brute berserks in Halo 2, they are disabled of all jumping abilities. There are very few times where you can leave a brute pack member alive after killing the other members, without that brute going on a rampage. In Halo 3, they will put their arms outwards and run at the player and do a smashing type animation or jump at the player and do the same. When the player is in a Wraith or Scorpion, the Brute will either melee the hatch or attach itself to the tank's rear and repeatedly smash its head into the exhaust port.
However, this can be used to the player's advantage sometimes. Usually the Brute goes on rampage after it is wounded, and stops using its weapon, leaving it open to fire. Also, on Halo 2, the player may be able to get the Brute stuck in a corner, open for the kill. Jump Pack Brutes will sometimes use their jump packs while in a rampage to get closer.
The last surviving Brute of a pack will also go on a rampage, charging at its enemies in a blind rage. This may be due to the strong bonds with the members of their pack. A Brute, after calming down from its rage, will sulk and mourn the loss of its comrades, even caress the bodies of the fallen. However, upon seeing its enemy, the Brute will abandon its sulking mood and once again become enraged. This mourning is a rare occurrence, almost never seen in combat, and only when there is a brief lull in the fighting.
Changes from Halo 2 to Halo 3
Changes from Halo 3 to Halo 3 ODST
Changes from Halo 3 to Halo Reach
Changes from Halo Reach to Halo Infinite