During the course of Assassin's Creed, there are two types of guards: Soldiers and Archers. The archers are mostly the same, but there are three ranks of soldiers. All guards are armed with swords (with varying styles).
The ordinary soldiers don't wear helmets (Muslims wear turbans) and are only equipped with leather armor or light Lamellar armor. Guard archers are on par with ordinary ones except they are only found on rooftops, wear a hood, and use bows for a ranged attack.
Guard Sergeants (or elite guards) have helmets, the Crusader variant wear chain mail with a tunic, and Mujahideen Sergeants posess medium Lamellar armor.
Guard Captains are the most powerful guard besides the Templar Knight. The Muslim Captains wear Baidah helmets and heavy Lamellar armor where Crusader captains are equipped with chain mail and varying knight helms.
Templar Knights are a special version of guard where only 60 are found in game.They are similar to the Crusader guard captain except with higher stats and the fact that they only wear one version of helmet which appears bloodstained. They will also provoke a fight when they see Altair, no matters what his nortoriety level is. Strangely enough, Templar Knights can be found in many places, including Muslim cities.
All Muslim guards speak Arabic,ordinary Crusader soldiers and archers speak English, Crusader Captains and Sergeants speak French or German, and the Templars speak all of the dialects(but only speak Arabic in Altair's fight againts Robert's imposter).
The guards in Masyaf, despite being marked as an ally via Eagle Vision, function exactly like normal ones. They are equipped in robes similar to Altair's, but they only have a sword and their skirts are shorter. They have all five fingers, indicading that, though members of the order, they are not assassins themselves, instead serving as guardians.
In Assassin's Creed II, there are five types of enemy guards:
Regular Guards
Those are the "standard" type of guard which can be found almost everywhere on the ground. However, they use a large variety of swords and maces. Those regular troops are divided into three ranks themselves: Militia, Elite and Leaders.
Thugs are people hired by Vieri de' Pazzi to attack Ezio. While not officially or technically guards, they function in a remarkably similar manner. They will attack Ezio even if he is Incognito, and fight only with fists. After assassinating Uberto Alberti, they can no longer be found in game, except for the Courier mission Casanova.
Militia is the weakest rank. They wear no armor, and can be easily killed (with one counter-kill). They are also the most easily frightened during combat as after battles they are the first ones to retreat.
Elite guards are stronger, wear a moderate amount of armor, and need three counter-kills to be defeated. Elites are also more courageous than Militias.
Leaders are the best fighters and most tenacious of all the regular soldiers. They wear slightly more armor that their Elite counterpart. The Leaders will last slightly longer than Elites during Ezio's counter-attacks. They also hardly give up their weapons, making them harder to disarm than the others.
The Regular Guards are not especially agile, but can climb up to the rooftops in order to follow Ezio (while not as fast as him). Also, they can recognize Ezio sitting on a bench, but can be assassinated before they recognize him and spread word of his presence.
Seekers
The Seekers, also called "Paranoid" are one of the new special guard types. They are constantly looking in hiding spots (such as the haystacks, benches, and crowds) and checking them (although Ezio can assassinate the seeker from his hiding spot if that happens). They are armed with long spears or halberds, giving them an increased reach in combat. Seekers, like most of the other guards, wear armor. The armor they wear is slightly more than a Leader-ranked Standard, but less than a Brute. When unarmed they will occasionally approach Ezio from behind and then hold him while the other guards assault him.
Agiles
One of the new guard archetypes is the Agile, which, as the name suggests, is a very fast, light-armored enemy. They run faster than Ezio and also have the Free Run ability which can lead to chase sequences. They wield small weapons such as daggers and other short blades.
Brutes
The Brutes are heavily armored and equipped (two-handed weapons such as heavy swords and axes). Their armor covers almost every part of their bodies, making them tough to bring down, but also making them cumbersome and slow. They are not very intelligent, and won't be able to tell Ezio from anyone else in a crowd. When deflecting a short weapon, they will not take damage (while all other guards do), but can still be damaged with a short weapon. A good way to make short work of them is to disarm them and counterattack, because they are very easy to disarm. Brutes have two types of attack: one quick, and one that begins with a wind-up. The latter attack cannot be countered, and must be dodged, while the former can be countered. You must possess a Brute's weapon to counter the wind-up attacks of another Brute.
Archers
The Archers are guards that patrol and defend the rooftops. They are armed with bows and swords (sometimes maces instead of swords), and warn Ezio on sight to leave the place, no matter the notoriety. Approaching them will force them to draw their weapon out and commence a fight. Archers are seemingly just Militia-ranked Standards with the capability of attacking at a distance with their trusty longbows. While Florentine and Tuscan Archers can be killed with a single Throwing Knife, archers in the other cities and regions (such as Venice and Romagna) will need two Throwing Knives to be taken down. Since they are almost always on the rooftops on buildings, Archers are fairly easy to dispatch in melee combat as they have the skill and hardiness of a Militia-ranked standard, making them easy to kill. Another good way to dispatch them is to simply throw them off the roof, which will instantly kill the Archer if they fall more than two stories or if they land in water.
A Brute
