From Halopedia, the Halo wiki
Introduced in Halo 2, Brutes are aggressive foes characterized by their rage and brutality. They become the main enemy force after their introduction in the level Gravemind, and reappear in leadership roles in Halo 3, Halo 3: ODST, Halo Reach and Halo Infinite.
There are some general tips on how Brutes fight across the games. However, unlike their most direct counterpart the Elites, Brutes vary significantly between each of their game appearances in the way they fight and their ranks are structured.
As the name suggests, Brutes in the games rely on overwhelming force, utilizing the numbers of their packs in conjunction with their crude but undeniably effective firepower and their strength in melee combat. When at range, Brute shooting tends to not be very accurate, even with precision weaponry. To make up for this, they push their enemies into short ranged firefights or melee combat, where their weapons are more dangerous and they can use their overwhelming strength. This aggressiveness extends to vehicular combat as well; Brute drivers are more likely to try and splatter you compared to Elites, rather than sit back and shoot. Brutes are also capable of Hijacking vehicles, in the same way Elites are. That said, Brutes do display a grasp of basic tactics, with their higher ranks directing their allies to use outflanking maneuvers, using cover when under sniper fire, or throwing grenades to flush enemies out.
Brutes tend to congregate in large 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. As an example, a pack may consist of one Brute Captain, 1-2 Brute Majors and 2-3 Brute Minors, in contrast with squads of Elites, who tend to be in lower numbers when encountered without other species.
On the defensive side, while the armor of Brutes has changed throughout the games, in all incarnations the Brutes are durable foes, able to take more physical damage than Elites, though they are correspondingly less agile. They tend to take cover less often compared to other enemies, although they are prolific in the use of other defensive abilities.
As for weaponry, while their arsenal varies across the games, there are two kind weapons commonly found in their hands. Low ranked Brutes tend to wield short ranged automatic weapons, like the Brute Plasma Rifle or the Paegaas Workshop Spiker, which they use to soften their targets before dealing the finishing blow in melee. High ranked Brutes are often equipped with grenade laucher-type weapons, most famously the Brute Shot, which they use to force enemies out of cover, and to make up for their lower accuracy.
An ability that Brutes share across all their appearances is their tendency to go on rampages. A berserking Brute will usually throw away all its survival instincts, and charge out of cover to engage his foes in melee combat. This can be extremely dangerous, especially if the player is unaware of that it is raging, as a Brute can kill even a fully healthy player in 1 or 2 hits, which are delivered more rapidly than its normal melee attacks. This can be especially devastating for the player's AI allies; a rampaging Brute can kill an entire squad of Marines in melee and still be alive to engage the player.
Conversely, if the player is prepared, it can be a way to force a foe with a powerful ranged weapon to discard it and become an easier target. A rampaging Brute will never take cover, and rarely dodge even grenades or rockets thrown at it. On top of it, enraged Brutes will usually roar in place for a second or two, giving the player some time to stop their rampage before it even begins. It may be hard to score headshots though, as the Brute will move very fast, and his head will shake around.
The causes of berserk behavior can be slightly different depending on the game, but can usually be found across the following:
By far the most dangerous Brutes are Chieftains. Appearing first in Halo 3, these Brutes are the highest ranking of their kind in the games they appear in, in the same weight class as Hunters and Elite Generals. Chieftains are usually armed either with the Gravity Hammer, with heavy explosive weapons, of with detached turrets. They always have some form of head protection and energy shielding, on top of their very large health pool. To top it all off, they are never alone, often accompanied by a large number of other Brutes.
Chieftains wielding hammers will charge at the player at high speed, using their resilience to shrug off incoming fire as they try to smash him with their weapon; even a single strike with the hammer's shockwave is enough to kill a player at full health. Beware of fighting them in close spaces. Chieftains with ranged weapons will prefer to stay back and lay down a barrage of shots with their guns, either using their shots to force the enemy into cover for their pack to finish off, or using their allies to force the player into the open for them to shoot.
Brute Chieftains are enemies worth using heavy weapons on. Save up your strongest guns for these encounters. Depending on the configuration of the battlefield, it may be worth killing the Chieftain's fellows before taking him on, as they will otherwise catch you unprepared while you fight a dangerous enemy.
Game Specific Tactics
In their first outing, Brutes appear halfway through the game, in the level Gravemind.
In this game, no Brutes sport energy shields, relying on their high health to survive encounters. All Brutes wear a helmet, which must be shot off before a headshot can be scored. In general, headshots are the best way to deal with Brutes, bypassing their immense health. Only Honor Guards wear helmets that make them immune to headshots. In absence of precision weapons, the Needler is also very effective against them. The Energy Sword is capable of killing a Brute in one hit. While one may be right to think of using human weapons on them, the only time those can be used against them in mass is in the level High Charity, which is mostly spent fighting the Flood.
Low ranking Brutes fight the player using mostly Brute Plasma Rifles, occasionally wielding Carbines or human Shotguns. High ranking Brutes are mostly found wielding the dangerous Brute Shot. While sometimes they are scripted to enrage, Brutes in this game will always berserk when they are the last Brute in their squad. When they do so, they throw their weapons on the ground. Brutes hunch down significantly when berserking, almost running on all fours, and thus becoming a harder target to shoot in the head, especially from behind.
Brutes in this game take the place of Elites as the main leader enemies. As such, they have been given a significant overhaul. Brute body health has been diminished significantly, as they now wear Power Armor with regenerating shields. Contrarily from Elites, their armor falls to pieces when the shield is broken, leaving them vulnerable in a way Elites aren't. Brutes gain all new weapons that fit their fighting style. The Spiker becomes their main offensive gun, while specialist ranks can be found wielding the short ranged Mauler. Their main grenade is now the Spike Grenade. On top of that, several new ranks appear, covering various roles Elites had in previous games and more. Finally, this game introduces Chieftains as regular enemies, and the sole wielders of Gravity Hammers.
Brutes in this game prefer to fight from close-middle range. While they are less aggressive than in Halo 2, they make up for it in variety of tactics and weapons. Brute packs will frequently send a few of their number to force the enemy out of cover, or throw their grenades at walls behind them.
Brutes are also the only enemy users of Equipment, fielding everything but the Autoturret and Portable gravity lift. Most often, they will use the Bubble Shield or Deployable cover when faced with heavy fire, the Flare when charging at an enemy, and the Power Drain when faced by vehicles. Other equipments are used by their specialist ranks.
When their armor is broken, Brutes begin berserking, although no more than one Brute berserks at the same time. This can be used to strip multiple targets of their armor without risking (too much). Some circumstances however may bring a Brute to berserk even with their armor on. The use of the Radar Jammer sends them in a frenzy, and sometimes even high ranking ones will berserk if the player evades them for too long. When berserking, a Brute will sheathe his weapon, then crouch down in a wide stance and run towards the enemy. Depending on the distance, they may also make a jump holding their fists together in the air. Brute Captains enrage more rarely than their lower ranked brethren, but also have an additional kind of rampage behavior. When many of their fellows are dead, they may charge the player in a straight line while shooting their weapon at them, ending with a melee attack. This can be particularly dangerous if they are wielding a Brute Shot.
Halo 3: ODST
Brute behavior is mostly the same as the previous game, though there are a few differences. As the player's melee is weaker, it is even less recommended to face a Brute in close combat. It is also easier to recognize the remaining strength of a Brute's armor, as it now glows like usual Energy shielding. Also, while the player may be incapable of deploying Equipment, the Brutes have no such limitations. Brute Jumpers also gain two more ranks, the Major and the Ultra.
Compared to the previous games, Brutes have much less variety, appearing only in three ranks, the highest of which is fairly uncommon. They do not extensively sport Power Armor, and their stance has gone from upright to very hunched.
Though they do not have energy shields anymore, their base health has been increased to compensate. They also return to use head protections like in Halo 2, with the Captain's helmet having more health than the Minor's. Only the Sniper rifle can completely pass through. While the Needler remains equally as effective, Brutes will treat the Needle Rifle as a heavy weapon, and will dodge after even a single shot. Brutes have also gained the ability to use Armor Lock, which they employ to save themselves from heavy weapons, vehicles and supercombines. Brutes are immune to Assassinations and backsmacks unless they are unaware of the player.
As Elites are back, Brutes return to being very aggressive, moving quickly from cover to cover in order to get in melee with their enemies. This behavior is engaged regardless of their weapon, even Concussion Rifle wielders will move towards their foes. Gravity Hammers can also be encountered in the hands of Brute Captains, and they gain a host of moves with them, such as a double spin that doesn't cause a shockwave (but is still an instant kill on high difficulties).
Berserking is more subdued than the other games, happening mostly when an ally is slain near a Brute. Rampaging Brutes will flail their weapon for a moment before charging towards the nearest enemy while shooting as fast as possible, ending the charge with a melee attack. They will usually return to their standard behavior after a kill. However, be aware that more than one Brute can go berserk at the same time.
Returning as the main foes, though without supplanting the Elites, Brutes sport somewhat of a combination of their combat doctrine from the previous games.
All Brutes wear Banished Power Armor, which comes in both shielded and unshielded varieties across the ranks. All Brutes have a head protection that must be shot off before scoring headshots, and their armor protects them from body damage as well. The shields of their armor protect them from assassinations until depleted, and are always active (unlike Elite shields, that are kept inactive until they enter combat).
Brutes have an immense variety in their arsenal, with almost every single weapon being utilized across their ranks in the game. Knowing what each rank looks like and what weapon it uses is fundamental to survival. On top of this, Brutes have gained the ability to pick up weapons from the battlefield. Beware of killing weak enemies with powerful weapons near a Brute: he will pick them up and become a much bigger threat. Low rank Brutes can still be a considerable nuisance at range, as their Manglers can shoot far, with good precision, and pack a punch.
Spontaneous berserk behavior is pretty rare in this game, sometimes being triggered by leaving a wounded Brute alone. However, an entire rank exists that is always berserking. Brutes in this state run incredibly fast and hit very quick with their swipes. It is recommended to put distance between you and them using the Grappleshot, or to stun them with shock weapons.
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