To garrison a unit means to put it inside a building or unit.
There are several advantages to garrisoning units. Garrisoned units are safe from attacks until ungarrisoned and in Age of Empires II, will slowly heal. Once units are inside, the garrisoning building often gains an attack, or receives boosted attack values.
Units can also garrison in buildings belonging to another player that is allied with them.
Age of Empires
Age of Empires II
Units can be garrisoned in a building either by
- selecting the units the player wants garrisoned, holding ALT, and then right-clicking the building,
- selecting the units the player wants garrisoned, pressing the garrison hotkey (by default: 'G') and then either left- or right-clicking the building,
- having the right-click garrison option in the settings activated and simply selecting the units the player wants garrisoned and right-clicking the building, or
- setting the gather point of the building onto the building and then producing the unit the player wants garrisoned (production garrison)
Note that while a building is damaged to a certain extent (remaining HP ≤ 20%), it is impossible to garrison units inside it, and all units that had been garrisoned before the building was damaged are ejected from it.
There are two main types of buildings that players may use as garrisons: First, there are defensive buildings such as towers and Town Centers (alongside other defensive buildings such as Donjons and Kreposts), in which the player can freely (albeit with some restrictions based on unit type) garrison their units to take shelter in. Second, there are production buildings (such as Barracks, Archery Ranges and Siege Workshops) in which up to 10 units can only be garrisoned immediately upon their creation, by setting the gather point of the building onto the building itself. The castle falls in both of these categories simultaneously: While Trebuchets and Organ Guns cannot be garrisoned in a castle (or any other building) when they have already been ungarrisoned before, they can be garrisoned with production garrison; simultaneously, other units the castle can build can be garrisoned there as a defensive garrison.
A list of which buildings have which garrison type(s) follows:
- Town Center: Up to 15 Villagers, foot archers, and/or infantry (25 for the Teutons)
- All towers: Up to 5 Villagers, foot archers, and/or infantry (10 for the Teutons)
- Donjon: Up to 10 Villagers, foot archers, and/or infantry
- Castle1 and Krepost: Up to 20 of any non-siege unit (i.e. includes cavalry)
- House: Up to 5 Villagers (only for the Khmer)
- Harbor2: Ships (Malay only)
- Castle1: Trebuchets, Organ Guns
- Barracks2: Infantry
- Dock2: Ships
- Archery Range2: Archers
- Stable2: Cavalry
- Siege Workshop2: Siege weapons
- Monastery3: Monks and Relics
- If the gather point is set to the Castle itself, Trebuchets and Organ Guns can be garrisoned inside as an exception to the "non-siege" classification, but these units cannot reenter after ejecting. In other words – for siege units trained there, the Castle may function as a production garrison
- Monks may eject, but cannot reenter the building. Relics, however, may be garrisoned (by a carrying Monk) and ejected at any time. Garrison limit: 10.
Advantages of garrisoning units
- While garrisoned, units are immune to damage or conversion. If the structure is destroyed or heavily damaged (remaining HP ≤ 20%), they are dropped out of the building without taking any damage to this point. If a building with units garrisoned in it gets converted, all the units that were garrisoned in the building will be automatically ejected.
- Also, damaged units slowly regenerate health while spending their time inside a building. Castles in particular have a faster regeneration rate than other buildings; towers heal garrisoned units 0.1 health per second, while Castles heal twice as fast, at 0.2 health per second. Researching Herbal Medicine further increases the regeneration rate.
- Also, garrisoned Villagers and archers increase the damage output of Watch Towers, Guard Towers, Keeps, Bombard Towers, Castles, and Town Centers. That is very useful considering the fact that the garrisoned units do not take damage while dishing out plenty of their own.
- Finally, if the enemy scouts a building or has Spies researched, garrisoned units inside buildings will keep opponents guessing as to the true makeup of a player's army since there are always just flags on top of the building, no matter what kind of units or how many units are garrisoned inside.
There are special commands relating garrisoning. The player can command all Villagers to automatically find the nearest defensive garrison and go inside by ringing the Town Bell. Issuing the command again will send the workers to the task they were previously doing before the Town Bell was rung. This takes into account the capacities of the player's buildings. If the player does not wish to order all the Villagers to garrison, it is possible to order Villagers at each building to "return to work" separately.
Units tend to be ejected or ungarrisoned at the south side of the building (in front of the building sprite) unless a gather point is set, in which case they will be organized in a way that they are on the closest side of the building to the gather point.
Garrisoned units generate extra arrows according to the units inside. These extra (secondary) arrows may have different attack bonuses compared to the main arrow projectile. The number of extra arrows is denoted inside the parentheses next to the building's attack. Since update 50292, the number of extra arrows is given by the following formula:
where DPS, the damage per second, is the quotient between the arrow's pierce damage and the reload time of the unit/building. The calculated value is rounded down to the nearest integer.
All defensive buildings have a limit to how many extra arrows they can shoot. Towers can shoot 4 extra arrows (8 for Teuton Towers), Donjons can shoot 4 extra arrows (6/9 in the Castle/Imperial Age to a total of 7/11 extra arrows), Town Centers can shoot 10 arrows (15 for Teuton Town Centers), and Castles and Kreposts can shoot 16 extra arrows (to a total of 20 extra arrows).
For the DPS of defensive buildings, a secondary arrow is considered instead of the main arrow. While this makes no difference since they all do the same damage, it did with Kreposts before update 54480 since their secondary arrows did 11 damage while the main arrow did 9 damage (now they all do 10 damage). As a result, Kreposts would shoot the same number of extra arrows as a Castle would. This distinction between main and secondary projectiles is also relevant for towers, as their secondary projectiles deal other bonus damage.
Researching Thumb Ring most likely increases the number of extra arrows generated, since it increases the DPS of archer units. The Ethiopian, Mongol, and Spanish civilization bonuses have a similar effect.
Villagers and Teuton infantry (the latter provided Crenellations is researched) units contribute 2.5 DPS each. While rounding and upgrades can in some cases reduce the raw DPS, garrisoning may have other advantages such as increasing range, decreasing the effect of pierce armor, or protecting the units from attack.
The Japanese unique technology Yasama increases the number of extra arrows fired by Towers by 2, so Japanese Towers can shoot a maximum of 6 extra arrows. The Malian unique technology Tigui increases the number of arrows fired from a Town Center by 5, so Malian Town Centers can shoot a maximum of 15 arrows.
Prior to update 50292, it was generally a bad idea to garrison Chu Ko Nu and Kipchaks, as the pierce damage of a secondary arrow was used to calculate the number of arrows instead of the main arrow. Since update 50292, units which fire multiple projectiles now add the correct amount of extra projectiles to fortifications when garrisoned inside them. Counting all projectiles, both main and secondary, Elite Chu Ko Nu and Elite Kipchaks have the highest DPS among all archer units and, for a Castle to fire all 20 extra arrows, it is enough to garrison 13 and 14 of them, respectively.
Some units can also garrison other units:
- Transport Ship: Up to five units (+5 with Careening researched, another +10 with Dry Dock researched; +5 for the Saracens)
- Battering Ram: Up to four Villagers and/or foot soldiers
- Capped Ram: Up to five Villagers and/or foot soldiers
- Siege Ram: Up to six Villagers and/or foot soldiers
- Siege Tower: Up to ten Villagers and/or foot soldiers
Unlike with buildings, garrisoned units are not ejected if the garrison unit is heavily damaged. If a unit with garrison is converted, the garrisoned units are not converted, but stay inside the garrison unit. Only the new owner can eject the enemy units.
Units garrisoned in other units are not healed, even if they can regenerate.
- How Many Projectiles Do Garrisoned Buildings Shoot? T-West, 2021
- Should You Garrison Archers In Towers? Spirit Of The Law, 2019
- Chu Ko Nu, Kipchaks, & Castles (extra projectiles) Spirit Of The Law, 2021
- The unconstructable buildings Fortress and Poenari Castle can also hold up to 30 and 25 non-siege units, respectively.
- The stats of a Teutonic Sea Tower indicate that it can hold five units inside, but no units can actually garrison in it. This is because all Teutonic towers add an additional five units to their garrison stats, but Sea Towers are a type of tower that cannot hold any units.
- The stats of Trade Workshops and Mosques indicate that they can hold ten units, but there are no apparent units that can enter. The Trade Workshop has this feature since it was originally supposed to hold Villagers inside for converting resources to Trade Goods, but this idea was scrapped and the garrison count remains.
Age of Mythology
In Age of Mythology, the buildings in which players can garrison units are:
- Town Center/Citadel Center: Up to 25 worker, foot archer, and/or infantry type units
- Dock: Up to 10 naval units
- Sentry Tower/Watch Tower/Guard Tower/Ballista Tower: Up to 5 worker, foot archer, infantry type units, and/or heroes (including mounted heroes, such as Contarius Hero)
- Manor: Up to 5 worker, foot archer, infantry type units, and/or heroes (including mounted heroes, such as Contarius Hero)
- Castle-type buildings (Fortress, Migdol Stronghold, Hill Fort, Palace, Castle): Up to 10 worker, foot archer, infantry, and/or cavalry type units
- Lighthouse: Up to 5 worker, foot archer, and/or infantry type units
- All military buildings can garrison trained units but only upon creation.
Some general rules about garrison differ from Age of Empires II. Units may only garrison into a building once its construction is completed but can enter and exit at any time. If the building is destroyed or removed, units will be ejected and line up around its perimeter or head to a gather point designated for that building, prior to being destroyed. The gather point can be another building in which units can garrison. Units garrisoned in a building will not regenerate HP and cannot be healed by healers but they can remain within regardless of how much HP it has left. Defensive structures (except for towers) do more damage as more units garrison in them. There needs to be at least one ship garrisoned in a Dock for it to be able to attack. Units that are garrisoned within a building are not only protected from attacks but also from all god powers. Monks cannot convert units garrisoned in a building.
The following units can also garrison other units:
The Helepolis and Siege Towers are the only siege weapons in which units can garrison. The Helepolis gains extra damage from units garrisoned inside, while the Siege Tower does not. These are especially useful for maps with large natural obstacles, such as Jotunheim (cliffs), Islands (water), and Deep Jungle (trees). Here, players can garrison units in the siege weapons then garrison the siege weapons in transport type units, reducing the amount of the latter that need to be trained. Both siege weapons can garrison up to 5 worker, foot archer, and/or infantry type units.
Each civilization has its own variant of a Transport Ship. These can initially only garrison 10 units (12 for the Atlanteans) but that number doubles if Enclosed Deck is researched. The Norse arrow ship, the Longboat, can garrison 5 units, which can also be upgraded by Enclosed Deck. Furthermore, the Egyptians can train two myth units that can act as transports. The Roc (the only airborne transport) and the Leviathan can garrison 15 and 20 units, respectively. These units are a more risky means of transport because if they are sunk or killed, all the cargo they carry will be killed as well.
Charon’s Ferry and the Pirate Ship are transports that are exclusively encountered in the Fall of the Trident campaign. The Raft and Monkey Raft are Easter egg transports that can be found in the Scenario Editor.
Age of Empires III
- Agra Fort1: Up to 50 villagers
- Blockhouse1: Up to 20 villagers
- Castle1: Up to 40 villagers
- Dock2: Up to 20 Fishing Boats
- Fort1: Up to 50 units
- Nobles' Hut1: Up to 15 villagers
- Outpost1: Up to 10 villagers
- Town Center2: Up to 30 villagers
- Village2: Up to 20 villagers
- War Hut1: Up to 20 villagers
- Kallanka3: Up to 10 military units; take up 1 less population when garrisoned within.
- Stronghold: Up to 50 military units
- These buildings receive a boost to their attack in proportion to the units inside. Once the Town Bell is rung, villagers will run there and garrison inside the closest available defensive structure or Town Center. Once the danger is over, the Bell may be rung again to release all villagers and send them back to work.
- These three buildings are in a special category because they lack an attack by default, though this is partially averted by the Town Center, which can use an anti-ship attack. Either way, Docks, Town Centers, and Villages require villagers to be garrisoned if they are to fire against nearby enemy units. The Village also requires a Home City Card named Village Defenses in order to be able to fire, supplied from the Chinese Home City Cards.
- Age of Empires III: Definitive Edition introduced the decreased unit population for military units garrisoned within a building ability.
Depending on the ship type, the amount of units that can be garrisoned varies:
- Fishing Boats: Up to 10 units.
- Flat-bottomed Boats*: Up to 15 units.
- Canoes and Marathan Catamarans: Up to 20 units.
- Tlaloc Canoes: Up to 40 units.
- War Canoes : Up to 50 units.
- Standard military ships can garrison up to 50 units. This also includes Morgan's Flagship* and Lizzie's Flagship*. They can garrison any land unit in the game, including artillery, herdable animals, and wagons.
* Campaign scenario-exclusive units.
Age of Empires IV
In Age of Empires IV, infantry, cavalry, siege, and boats can garrison within certain buildings and/or units.
- Town Center: Up to 10 (20 for Capital) Villagers, infantry, and/or cavalry.
- Outpost: Up to 5 Villagers, infantry, and/or cavalry.
- Wooden Fortress: Up to 8 Villagers, infantry, and/or cavalry.
- Keep: Up to 15 Villagers, infantry, and/or cavalry.
- Dock: Up to 3 Fishing Boats.
- Battering Ram: Up to 16 Villagers and/or infantry.
- Siege Tower: Up to 8 Villagers and/or infantry.
- Transport Ship: Up to 16 Villagers, infantry, cavalry, and/or siege.
Each unit garrisoned inside a building adds a bow weapon that deals 6 ranged damage every 2.50 seconds.
In Outposts, maximum range of garrison arrows is 6.00 tiles (8.00 tiles after researching a weapon emplacement). In Town Centers and Keeps, maximum range is 8.00 tiles.