This is a guide written by Asjo for the .EN forums.
Defense is pivotal in a conquest universe, unless you are surrounded by active alliance-members who can retake your city within 12 hours of its capture (normally, it's 24 hours, but this is a 2x speed universe). Granted, no matter how are you defend, some people can capture your city if they want to, but the point is to discourage attacks and make sure other targets would be more viable.
While your city is still small, you main worry will probably be that of being farmed (attacked for resources/battle points) by bigger player. Bigger players will attack you to gain battle points and possibly to take your resources. The key to making yourself an unattractive target is to have a high level city wall, which will make your defender much more cost-effective and thereby my attacks less cost-effective. Therefore, the attacker would rather attack someone else, with worse defense and lower city walls. Once your city grows beyond 5000 points, you will want to have both tower (depending on city strategy, see multi-city guide) and level 25 city as it will otherwise be a juicy target because of being such a big city. Having such good defenses also means you can focus a bit less on defensive troops and spend more of your available population on attacking units.
Defensive unit mix
When you create defense, you have to consider the defensive properties of units. It's important to have the right mix of units to defend against different attacks. One thing you should probably take note of is the armies of the big players close to you, since they will be the ones trying to farm you and they will also be the most likely to launch a conquest attack, since a city close to their own might be convenient and with short travel distance they will be more likely to succeed. Therefore, if you adjust your unit mix to their army rather than making a "generalized" unit mix, it will likely benefit you. Mind you, if you have a big defensive army, it should not be necessary to adapt to individual players like this.
You can espect mainly to face two different kinds of attacks: attacks with only one unit-type (this is people who have a big offensive army and have enough units of one type to overwhelm you) and attacks with three unit-types times but with one main unit type (this is people who attack with their full army to have overwhelming numbers, but who prefer one type of unit). To rank which kind of units you are likely to defend against:
- Mythical units
If you look at the Grepolis unit table, you can see the attack-type that these units use. There are three different: blunt, sharp and ranged.
Slingers are ranged attackers, so you need defenders who do well against them. Swordsmen are the perfect counter to slingers since they have 30 in ranged defense. However, if you only have swordsmen, the attacker will see this when he spies you and simply attack with another type of units. Since swordsmen only have 8 in defense against sharp attacks, chariots or hoplites do very well against them. So, this means that you have to have something against sharp units as well. Archers are the units you want to use against sharp units, since they have 25 in defense against sharp units. Someone might attack with horsemen, so you need something to defend against blunt attacks as well. Here, your choice is between chariots and hoplites. And thus, you will end up with a balanced mix of units for defense, since you never know what you will be up against.
While you are certain that you need swordsmen and archers, some people prefer either chariots or hoplites. If you compare the two units in their overall defensive values (stats against all attack-types combined), it looks as such:
- Cost: 225
- Overall defense value: 37
- Resources per defense value: 6
- Cost: 960
- Overall defense value: 148
- Resources per defense point: 6,5
As you can see, hoplites are slightly cheaper for defense. In terms of population cost, both units are completely even, with 37 defend points per farm space. What could make chariots preferable, though, is that they are really good against horsemen and so will likely be able to discourage attacks from those (mostly relevant in a situation where you are being raided from the same island). Hoplites are more general defenders, only with a slight weakness against ranged attacks. However, one thing that you have to keep in mind is that hoplites and chariots are versatile units that can be used for both attack and defense. If you compare attack values, chariots cost 17,1 resources for every attack point while hoplites only cost 14 resources per attack point. Once again, hoplites are cheaper, but do keep in mind that chariots are faster when you attack on your own island, can carry more loot (8 times as much, despite only costing 4,2 times as much) and are less likely to die in marginal situations you attack a weak defender who might be able to kill two hoplites but cannot kill a chariot. Another factor to consider is your resources balance. If you find it hard to balance your resources while using hoplites for defense (and occational attacks), you might want ot use chariots instead. Save for a few special situations, I would always recommend that you use hoplites. The most important difference is that they are better attackers as well the fact that you can compose a stronger balanced defense using hoplites because you get to include more swordsmen (which have a higher defense value per population than archers). And keep in mind that if you use hoplites, you save the eight research points that you would have to use to get chariots.
So, if we need to define a balanced defensive. Early game, you will be more likely to face hoplites than horsemen, so a good ratio good be:
10 swordsmen / 5 archers / 5 hoplites
If you combine all the defensive values, you will have the following ratio:
- Blunt: 260
- Sharp: 265
- Ranged: 395
This defensive is best against ranged attackers, since you will be most likely to face them and since an attack solely consisting of slingers will be more powerful (as slingers have more attack points per population that other attackers). However, it is not too weak against blunt nor sharp attacks.
Normally, you will need mostly to defend against attacks that mainly have slingers and horsemen, though. So, instead, the ratio should look like:
10 swordsmen / 3 archers / 7 hoplites
- Blunt: 284
- Sharp: 239
- Ranged: 385
Depending on how often you are attacked by horsemen, you can decrease or increase the number of archers or hoplites. While hoplites only provide 37 defense points per population against the 43 defense point per population of archers, they have the added advantage of being decent attackers as well. You should never count out the possibility of being attacked with sharp attackers. If people have mixed offense/defense cities, they will often include whatever hoplites they have for defense in a city to attack along with their horsemen and slingers. And if you have no archers, you leave yourself vulnerable to a manticore or medusa nukes, both being very strong sharp attackers that people often build a lot of in one of their cities if they have a lot of favor (mostly relevant in older worlds).
When you are being attacked, always make sure to activate militia (city overview → farm → enlist), unless you don't want to show that you are online or suspect that you might need the militia against a conquest attack that is yet to be launched. The attacker will not gain any battle points for killing militia, but you will gain battle points for killing his units with your militia. Once militia is summoned, it will take three hours before they disappear and before you can summon militia again. So, if someone is attacking you with several attacks and it takes them more than three hours to reach your city, make sure to summon militia in advance (for instance, once the timer shows that there is 2:59:55 left for the incoming attack) so that you will have militia to face the first attack but can also summon the militia for the second attack).
Of course, if you have any good defensive spells such as Desire (-10% strength for attackers), Zeus' Rage (kills 10-30% of attacking units), Sea Storm (kills 10-30% of attacking ships), make sure to cast these. When you can them, you need to click on the icon for attack shown in your troop movement overview, not the city name, which is also clickable. However, if you think that a conquest attack might be incoming and don't want to give away that you're online, make sure you don't cast your spells too soon.
Role of offensive units
Any time you can, you will want to avoid defending with offensive units, since they are not at all cost-effective to defend with, while they still provide battle points for the attacker, making it more attractive to attack you. So, if you are being attacked, send them to support some 175 point city on your island to get them out of the city (or, if you can be online shortly before the attack, simply send it out of the city right before the attack and recall it afterward, which is a safer option). If you fear that attacks will come while you are offline and you want to keep your transport ships (these will be killed if an attacker managed to kill all your units and brings light ships to attack you as well) and offensive units safe, you can attack a 175 point player who is on a distance island so that the travel time means that the attack will return back when you are online again. Send all your offensive ships along with the offensive troops and transport ships. This is very effective since it also means that if someone captures your city, your offensive troops will attack him once they return. If your city is lost while your troops are out supporting another city, your troops will simply vanish.
If you have a lot of offensive units in your city, remember as a general rule to "fleetsave" them. That means that when you go offline, you send them to attack another city, preferably a low-point ghost town, with a timing that ensures they will able get back in your city around the time when you get back on. That means that you won't risk suffering terrible losses by someone trying to pick off your almost defenseless offensive units. For instance, if you have 250 light ships in your city, the attacker can kill those off while only losing 59 when attacking with a similar amount of light ships. If one of your own cities has the right distance, it makes for the perfect way to fleetsave, since you cannot attack yourself unless your city in under siege, so your units will simply return.
If you are trying to defend you city, what is the point of naval defense, you might wonder. Generally, I don't recommend building defensive ships in a city that you are either using for offensive troops, defensive troops of a mix of both. The reason I say this is because since you're limited in population, building biremes will take up too much population and make your city less effective in terms of offensive or defensive army. If you have a defensive city when you want some offensive troops, you will need transport ships and light ships if you want to attack people on other islands. The more biremes you build, the less light ships you could use for transport and the less offensive troops you could bring. If you're purely playing defensively, then building biremes will take population about from the defensive ground troops, making it less effective, while you could never have an effective amount of biremes (probably just enough so that any attack will bring enough light ships to kill them.
Normally, I would say that you should only build biremes when you specialize cities (see multi-city guide). Then you can have a city that only builds biremes and that can defend other cities really well. Once you have that many biremes, they can fight against smaller numbers of light ships more effectively and if you are in an alliance, a big number of biremes is great, since it can make your cities virtually unbreakable as long as the attackers don't have more light ships than you have biremes. The only trouble with having a city full of biremes, with no other troops, is that the only defensive bonuses they get come from the tower. So, if the attacker attacks your bireme city and has enough light ships, he can capture it quite easily, with minimal losses. Whereas the attacker would lose many more troops against a full defensive land force supposed by a big city wall, he might only lose the same amount of units as you when taking down your biremes. So, never assume a city is safe simply because it has a lot of biremes.
That said, if you have very stupid opponents who constantly send attacks at you without any light ship support, biremes can do great work. They will kill all the transports, meaning that the attacker's offensive troops never reach shore, but die before the battle. If you don't specialise cities, but have a lot of mixed offensive and defensive cities close to each other, it might be worth it to build 20-30 biremes in each so that you can send them the city that is being attacked and have a change of killing the attacker with a total force of 150 biremes. It gives you a bit of flexibility, while I generally don't recommend it. One way or another, you will likely need biremes on in conquest worlds (unless you know people who can help you), where you have to defend your siege when you take a new city. Another thing to mention is that you should never build triremes for defense. Triremes are expensive units, who don't really justify their cost. They can both attack and defend pretty well, so when you attack and city and put it under siege they can be quite flexible. Normally, you would just send biremes to defend your city once the siege has started, though.
If you look at the numbers of cost and population-effectiveness of triremes:
Triremes costs 23.3 resources per offence point (light ships cost 12) Triremes costs 16.8 resources per defense point (biremes cost 10.5) Triremes provide 11.2 offence points per population (light ships provide 20) Triremes provide 15.6 defensive points per population (biremes provide 20)
Most effective defenders (defense points per population)
- Cerberus 90
- Medusa 79
- Pegasus 62
- Centaur 55
- Cyclop 53,7
- Minotaur 51,1
- Erineys 41,2
- Manticore 20
- Harpy 12,5
Cheapest defenders (resources per defense point)
- Cerberus 2.1
- Pegasus 2.6
- Minotaur 3.3
- Centaur 4.1
- Cyclop 4.2
- Medusa 5.2
- Erineys 5.5
- Manticore 12
- Harpy 19.2
Note that it is not advisable to ever mass units such as the cyclops or centaurs for defense, as they are unbalanced defenders, and will very easily die against specific attackers. Pegasi are only really effective in big numbers when you know that the attacker is mainly using horsemen, but have the advantage of flying.
Medusa and minotaurs are some of the most balanced defenders, and can be massed for defense. Medusas still need the support of a small number of swordsmen and minotaurs need the support of a small number of archers and swordsmen to act as a balanced defense, Cerberi are amazing defenders (one is basically equal to 52 swordsmen, even though it only takes up 30 population), but need the support of a good deal of hoplites and archers far a balanced defense. Here are the ratios:
Cerberus defense: 25 hoplites, 10 archers, 1 cerberi (34% blunt/21% sharp/45% ranged)
Medusa defense: 20 swordsmen, 1 medusa (37% blunt/24% sharp/39% ranged)
Minotaur defense: 10 swordsmen, 10 archers, 1 minotaur (35% blunt/25% sharp/40% ranged)
If you use the suggested ratios, a maxed out defense with cerberi or medusas will be both be around 30% stronger than an equivalent normal defense. A minotaur defense will only be 9,4% stronger than a normal defense.