They have access to all cavalry techs. Their unique unit, War Elephant, is a unit that is slow and expensive but with a large area of attack and massive amount of hit points.
They are one of the only two civilizations in the game to possess all the final gathering-rate technologies, the other being the Byzantines. This obviously allows for an all-round economy in matches where the Imperial Age is played extensively.
They have the weakest infantry in the game, missing both the Two-Handed Swordsman and Champion upgrades for their infantry. In addition War Elephants are slow and very vulnerable to conversion by enemy monks. Since the Persians cannot research Heresy the enemy could amass an army of War Elephants of their own.
Even though building Cavalry Archers is viable for the Persians thanks to them accessing Parthian Tactics, the Persians lack Bracer.
Persians have a different start up than other civilizations, +50 Food and +50 wood, this means that they can build an additional house at the beginning or just gather another 50 Wood for their Lumber Camp or their mill saving gathering time, the same goes for the extra food that is just enough for an extra Villager. Persian town centers also have a better work rate than other civilizations, starting in the Feudal Age so a Persian player can spawn their Villagers a little faster, giving them an economic edge. This start-up bonuses allows to the Persians to perform well Feudal rush techniques, or go for a fast castle since aging up is also sped up. Persian Town centers also have more hit points, this bonus allows the Persians to defend better in early game. Unlike other civilizations Persians can perform a really strange rush commonly known as The Douche Persian Rush which consist on creating several villagers, gather wood and stone in order to delete their town center in dark age and rebuilt it near to the opponent base, Persian town centers have more hit points so it will stand for long time and the villagers should then build towers and steal enemy resources.
Normally a Persian player will focus on the cavalry, Persian Knights have attack bonus against archers, and they have also full blacksmith upgrades for cavalry, this make their cavalry excellent for countering ranged units. Their expensive unique unit, the War Elephant, is a slow melee unit with a lot of hit points. Such characteristics make them considerably versatile: they are excellent against buildings and suited for even the most pitched battles. In fact, thanks to their trampling damage, they can damage multiple units simultaneously. Although very powerful, this unit is not invincible and can be countered with masses of Halberdiers, Camels, Archers and monks, so the player must always remember to support their elephants: the high cost per unit makes losing War Elephants even more painful. If dealing with enemy Halberdiers, War Elephants must be paired with Hand Cannoneers plus Scorpions if the resources allow it; if dealing against monks, which pose an enormous threat to War Elephants, the player must create some scout cavalry.
In water maps the Persians must take over since early game, their work rate bonus for their docks gives them an edge in this area, allowing for large fleet to be created quickly.
Persians being reliant on cavalry of course benefits from Team bonuses that furthers their uses such as the Frank team bonus (More line of sight for Knights) and the Hun Team Bonus (more work rate for the Stable).
Allying with Italians lets Persians train the Condottiero, which can take the place of the weak Persian infantry. Their speed make Condottieri ideal for repealing enemy Halberdiers and Camels. An allied Hun player is also good for Persians because of the faster stable bonus. Britons can be of great use if the Persian player wants to fields a lot of cavalry archers. As they lack proper defense against monks, the Teutonic conversion resistance bonus is helpful if the enemy counters war elephants with monks. Considering the high cost of the War Elephant and the heavy cavalry overall, Byzantine team Bonus is also helpful as it furthers the monks ability to heal increasing the lifespan of both paladins and War Elephants. As a gold hungry civilization Persians should also consider to have Aztecs as allies as their team bonus increase the relic gold generation, along with Burmese in order to favorably get at least a relic thanks to the revelation of these items, Spanish trade cart team bonus should also being considered, and last but not least having a Portuguese ally since they can generate gold through the Feitoria and send them to their allies through tribute.
Berber allies also offer fast, gold-free Genitours ( who fare better than skirmishers when paired with cavalry), and Kasbah, allowing Persian players to spam their War Elephants quicker than before (Considering War Elephants creations speed is slow), in exchange for melee support from Persian Paladins and Halberdiers.
In Water maps, there are two civilizations that should be in high consideration as allies: Malay and Vikings. Malay allies grant Persian players far-sighted docks for fast-response garrison fleet and coastal defense, as Malay have several boosts to the Infantry (free gold militia line and Karambit Warriors) they can also cover that weakness the Persians have. Vikings on the other hand offers their cheaper Docks as a team bonus, this of course benefits to a great extent the Persian docks who already have a better work rate, similarly to Malay, Vikings also can cover the infantry poor line the Persians have with their resilient infantry units.
Vietnamese players can also create win-win synergies with their Persian teammates. Persian War Elephants and other cavalry can screen Vietnamese archers since the Castle Age, while allowing the latter to snipe enemy Monks or bar enemy Pikemen and Halberdiers to close in at relative ease. In return, once advanced to the Imperial age, with Elephants and Bombard Cannons as their common components, the Vietnamese can mass-produce Champions, Imperial Skirmishers, Rattan Archers and other archers quickly by free Conscription, plus grant their Persian teammates decent bankroll via Paper Money, while receiving Cavaliers enhanced with anti-archer expertise, plus extra joint support from Persian Camels, Paladins, Halberdiers, Hand Cannoneers and advanced Cannon Galleons as lucrative rewards.
The War Elephant being a well rounded unit that have trample damage and a high amount of HP counters almost all types of infantry (except Samurais, Halberdiers, Viking infantry with Chieftains and Kamayuks see in disadvantages) even the infantry from prominent infantry civilizations like, Teutons, Burmese, Malay, Japanese, Goths, Malians, Slavs and Celts. They also counters practically all kinds of melee cavalry ( except Camels and Saracen Mameluke) even the cavalry of prominent cavalry civilizations, like Huns, Franks and Burmese, they are statistically superior on combat to the four versions of the Battle Elephant (which is only available for Khmer, Burmese, Malay and Vietnamese). They can even be used against buildings as a siege replacement, even civilizations like Byzantines, Incas and Koreans should take their precautions against them. It can also take a lot of arrow-fire so Persian War elephants can also punish civilizations reliant on foot archers such as Vietnamese, Britons, and Mayans.
Being a civilization with good mid and late game and able to boom their economy they can defeat civilizations that fare otherwise in closed maps like Black Forest (regular or bad late game, regular mid game, but good early game) like the Aztecs, the Huns and the Malians, especially if starting at Castle Age onwards.
As their Knights have more attack vs Archers, they can punish civilizations reliant on them like Mayans, Chinese and Britons.
As they have a Town Center with more HP and better working rate and more initial resources, they can perform a Town center Rush so in open maps they have an advantage over civilizations with poor early game such as Portuguese, Spanish, Indians and Turks.
Regarding the naval Warfare they are in advantage in the early game against civilizations that rely on their late game navy such as Portuguese, Spanish, and Koreans as they can spam their ships faster than these civilizations.
Defensively speaking their Castles are better defended against Rams in the Castle age thanks to the Boiling Oil technology (Rams are probably the best counter to Castles in the Castle Age) as well Town centers and Docks have better HP.
Despite being a very versatile unit due to their impressive statistics, the War Elephant have several disadvantages. As Persians lack Heresy, and the War Elephant itself is a huge and slow target they are very weak vs monks, so civilizations that make use of them like Aztecs, Spanish, Slavs and Burmese may convert them and use them against the Persian player even being able to amass their own War elephant Army if the Persian player doesn't take his previsions against monks if he decides to use War Elephants. War elephants are also very expensive so civilizations with cheap units or civilizations that can amass Halberdiers such as Goths and Byzantines can also counter them. Incan Kamayuks, Japanese Samurais and Viking infantry after Chieftains are also a threat to War Elephants. Ranged and fast units like the Cavalry Archers, the Malian Gbeto, the Saracen Mameluke, the Spanish Conquistador, and the Burmese Arambai can also counter them by hit and running them. Camel based civilizations such as Indians, Malians and Berbers can also counter War Elephants if they amass their Camels, Italian Genoese Crossbowmen can also counter War elephants especially if massed.
Since they don't get access to Two-Handed Swordsmen their infantry line falls fast against archers and infantry from other civilizations, also considering this fact they fare poorly at trash wars since they don't have a proper counter against trash units, so civilizations with good trash such as Magyars, Berbers, Vietnamese, Malay, Byzantines and Aztecs can overturn them in the late game when gold is scarce. Civilizations with anti-infantry units or with access to the Hand Cannoneer can eat through Persian Infantry. This includes Indians, Portuguese, Turks, Mayans, Incas, Aztecs, Byzantines and Spanish.
Despite having castles improved with the Boiling Oil technology and bulkier Docks and Town centers, Persians fall apart against civilization with good siege engines especially civilizations with good late game siege engines as they lack several key defensive technologies, Civilizations like Turks, Celts Ethiopians, Huns and Mongols can deliver nightmarish armies of siege weapons and anti building units against Persians.
Despite having good start up Bonuses and good economic bonuses they are at disadvantage in open maps like Arabia against civilizations with early aggression such as Huns, Aztecs, Magyars, Mongols and Goths since most of the Persian bonuses start to kick out in Castle Age onwards. Regarding the Town center Rush, Persian players should also consider that there are other civilizations that boost either the HP or the Attack of their Town centers while at the same time there are civilizations with other defensive bonuses that can counter their rush more easy than other civilizations, such as Teutons (their town centers can garrison more villagers so it can fire more arrows than the Persian one), the Byzantines ( who also have a bonus for their buildings making their town center the second bulkier one after the Persian) and the Incas ( which Blacksmith technologies benefit their villagers so they can attack the Persian villagers intending to create a Town center next to them)
Despite they are at advantage in early game in water maps thanks to the Dock work rate bonus, late game they may fell apart against civilizations with cheaper ships (like the Vikings and all the civilizations with access to Shipwright) or either a sustainable late game economy (like Malay and Portuguese both of which have their respective unlimited resources bonuses).
As their Town Center has more HP, Persians may get a slight advantage in Nomad maps, if they luckily enough place their initial Town Center near the initial Town Center of an opponent, making their Town Center rush almost as the game starts.
In Budapest map, as every player have double start up (2 Town Centers, double villagers, and 2 scouts) they also get an advantage, considering their Town Center work rate. Of course in this map is a bad idea to make a "Town Center rush" if starting from Dark or Feudal Age, as for that the player must delete their Town Center and place it near an opponent, and in this case the player should delete both to perform that.
If playing Regicide as players start with a Castle, they slightly have an advantage until the opponents reach Imperial Age thanks to the Boiling Oil technology.
Town Centers have more HP and better workrate, so Persians have an advantage early in Sudden Death games, as the objective in this game mode is to destroy the opponent's single Town Center (in this game mode, players are limited to just one TC).