We get asked all the time what troops are best for city defense, siege armies in GvG, or to place into GvG sectors as Defensive armies (DAs) - short answer is for most ages 8 artillery is one of the best to use as a siege or DA - no one likes to see a field full of cannons facing them. 

Understand that when we talk about diversity in the DA's of a GvG sector, we don't mean WITHIN the 8 unit armies themselves, we mean do not put the same thing in all the slots of a sector. If it's all the same, one attack army can easily kill them all.

For example: 

1 army of 8 artillery and 1 army of 8 light units is stronger than
2 armies of 4 artillery and 4 light units each mixed in each slot

• in scenario 1, I'm either going to have to switch between artillery and fast units to kill the 8 artillery, and attack with heavies to kill the 8 light units, or take big losses if I auto fight and take my chances with 1 attack army optimized for one of the DA but not the other.

• in scenario 2, I can probably just load up heavy or champs and power through all of it without switching my attacking army.

Fighting tactics vary for each age and the abilities of units from each age change too; Iron through Industrial Ages operate all on the same basic unit principles and are similar for fighting tactics. From Progressive Era onward, it changes as to what unit types work best against other types and higher ages have some peculiarities for each one.

While it can be a viable strategy to use some rogues (not all rogues!) in defenses in gvg (iron thru indy ages only, after PE and battlefield scale changes rogues take 3 turns just to cross the field and die long before they get there) but it is NEVER a good idea to put rogues in your city defense! In GvG people hurry and rogues can sneak up and take out units before they have been transformed, in city defenses your hood is not usually rushing to fight and it's easy to kill off other troops and leave rogues for last; rogues make really bad city defenders.

Iron Age (IA) 

• 8 ballista is still the king of DAs and sieges.

• You can also do 6 or 7 ballista and a drummer or two, makes it tougher to auto battle against.

• 8 archers can be quite annoying also and makes a good siege army as it's not easy to auto battle that even with horses.

• 5 drummer 3 rogue is a good one also, drummers are pretty mean in iron age and work well.

• If you're going to mix rogues in for DA's in a sector, that works fine iron-indy ages, but not at all from PE onward.

But don't fill a sector all with DA that are mostly rogues in all the armies, or someone can just kill the whole sector with 4 ballista 4 rogue on auto. This is true for every age. Too many rogues is just a waste of rogues and too easy to be killed.

EMA 

• Same as Iron really, 8 catapults are king. 

• 8 mounted archers can be quite annoying defense also in a sector, but it's easy to defeat as a single army siege (just use 1 heavy 7 rogues and hit auto, very simple to defeat as a siege but annoying when in a sector with other types of armies.)

• Drummers still work ok in EMA for siege or DA, mixed with rogues or catapults, but they really don't hurt much in any later ages and are just used as filler or 'junk' sieges after EMA.

HMA

• 8 trebuchets is the toughest DA or siege.

• 6 trebuchet and 2 crossbows is also a tough DA or siege army.

LMA

• 8 cannons is a tough DA

• 8 longbow archers also tough.

• for sieges 8 cannons or 1 cannon 7 rogue can be surprisingly tough because of the LMA range of cannons being less than most artillery in other ages, means on auto 1 cannon 7 rogue can hurt as much as fighting 8 cannons, sometimes more because it's also hard to fight all those rogues with horses or champs on auto.

COLONIAL (CA)

• 8 field guns is probably the toughest DA or siege army. Are we seeing a pattern?

• 1 or 2 rangers plus rogues is also a tough one for sieges, because the rangers hide.

• 8 muskets also a tough one, sometimes tougher to defeat than 8 artillery on auto.

• 3 heavy 5 rogue seems to throw some people off if they don't happen to have artillery, otherwise it's an easy one to kill. There are some other variations of this that can make for tough DA's or sieges, like 1 heavy 2 ranger 5 rogue, and so on.

Armies that can be easy to kill when facing just 1 army in a siege are not so simple if there is variety of armies placed in a sector, as discussed at the beginning.

INDUSTRIAL (INDY)

• 1 or 2 jaeger and rogues may be the toughest thing in indy to fight in GvG, especially on auto.

• 1 jaeger, 1 rifle, 6 rogues is a particularly tough DA to fight.

• 8 breech loaders is a really tough DA also, following the pattern of other ages.

• 8 rifles works for DAs too especially when it's not the only DA (for same reason not a great siege army, pretty easy to kill rifles with jaegers and rogues on auto)

Some combination of above would be a good city defense, breech loaders plus jaegers or rifles.

PROGRESSIVE (PE)

• 8 artillery is a great DA, or siege army, almost every age!

• 4 conscript 4 sniper is a good DA - tough on both tanks and conscripts

• 4 artillery 4 sniper also good for the same reason - tough on tanks and conscripts.

Even better if you're filling a couple of slots, 8 artillery in one and 8 sniper in the other, can not kill both of those without taking losses or switching attack armies.

MODERN (ME)

• 8 artillery is a great DA, or siege army, almost every age!

• 8 bazooka is also quite tough can really only be beaten by 4 artillery 4 rogues or even 8 artillery as an attack army.

• 8 paratrooper must be killed by tanks, mix that and bazookas in a sector to give enemies a headache.

POSTMODERN (PME)

• 8 artillery is a great DA, or siege army, almost every age!

• 8 commandos (paired with 8 artillery) makes it tough and no one-size-fits-all army can attack both of those without taking losses.

CONTEMPORARY (CE)

• 8 assault tanks is the best and really only DA worth placing in CE. ditto for sieges. Everything else is too easy to kill.

• 7 assault tank and 1 missile is also decent, sometimes if the missile makes a lucky shot it can cause more damage than the 8 assault tanks army.

• 8 missiles, only if paired with something else as a second DA, can really be annoying to fight next to 8 tanks because you must fight manually due to the tanks and wait for all the missiles to fire when you face the missiles. It's annoying and slows down attacks, which is the point of defense armies.

THIS IS ONE AGE WHERE THE ARTILLERY UNIT IS almost COMPLETELY USELESS. The missile leaves the battlefield after firing once, but 8 missiles is highly annoying when mixed within a sector - just don't use it for a siege, it can be auto killed with 8 helicopter very easily.

CE Champs are useless in GvG DAs and siege army, but quite formidable as City Army when you have high City Defense boost. Their attack is the same as Assault Tanks but their defense is significantly higher. Assault Tanks base defense is 90 while CE Champs is 125. With a High Boost 8 CE Champs is sturdier than 8 Assault Tanks in your City Defense!

TOMORROW (TE)

• 8 stealth tanks - no one likes to fight this.

• 1 or 2 stealth mixed with rogues is also highly annoying in TE and causes almost as much damage as 8 stealth tanks, sometimes more.

This is another age where 8 artillery is not a good DA really. it's easy to defeat with drones (flying can not be hit by artillery) and champs, and does not hurt stealth tanks as much as you might wish they did.

FUTURE (FE)

• 8 hover tank

• 3 rail gun, 5 hover tank

• 8 drone swarm good one to mix in a sector along with the hovers.

• 8 exoskeleton can also be quite tough as long as not by themselves in a siege.

ARCTIC (AF)

• Always include something flying, like 1 dragon drone, so that artillery is stumped since it can't hit flying units. Otherwise Plasma artillery and battle fortress rule the day for fighting and defense both.

OCEANIC (OF)

• Always include something flying, like 1 glider, so that artillery is stumped since it can't hit flying units.

• Turtles and hover tanks make a nasty defense army combo to fight on the AA map.

• For city defense I always threw in some eels since they hide, along with turtles, scimitar, subcruisers (good in defense because it returns fire).

VIRTUAL (VF)

• There are no flying units in VF, but the ninjas are annoying like eels were in Oceanic, because they move first, and hide. A few ninjas included in a DA, or 8 in a gvg sector, can be annoying as long as it's not the only army (otherwise easy to kill with ronin/heavies)

• VF really comes down to rockets or ronins, the other units are next to useless, but ninjas can be annoying if used properly in defenses.

Mars (SAM)

• Always include something flying, like 1 sentinel, so that artillery is stumped since it can't hit flying units.

• Mars is all about the heavy (wardens) and the fast (sentinel) units, for attack and defense. The spacemarines and tesla walkers can be a little annoying in DA's, but 8 warden or 7 warden 1 sentinel was generally the toughest city defense, and DAs in GvG just require mixing in enough sentinels so that 8 VF rockets can't auto kill everything in a sector.

Space Age Asteroid Belt (SAAB)

• The only unit worth anything in SAAB is the nail guns (ranged unit). 7 or 8 nail guns is the toughest thing to kill (used as a defense plus maybe a SAAB champ or Mars warden.)

• The fast unit in SAAB is a flying unit, so it's good to include one in a siege army or DA, just so that rockets can't be used for attacking it since they can't hit flying units, but otherwise the range on them is so bad that Mars sentinels are way more effective.

Space Age Venus (SAV)

• 8 energy cannon (fast units) is the toughest defense.

Space Age Jupiter Moon (SAJM)

• 8 abyssal gliders (fast units) is a tough defense.

• 8 harpoon grenadier (ranged unit) would also be no fun to fight because of their Contact skill.

• Maybe include one SAJM champ or fast unit (flying) in any defense army since the champ gives a boost to the other troops, and artillery in SAJM can't hit flying units.

Space Age Titan (SAT)

• 8 fast units is the toughest defense.

Space Age Space Hub (SASH)

• 8 ranged units (they have contact skill to retaliate) make for a tough defense.

• 8 fast units is also a good defense

• 8 artillery can be a brutal defense army to defeat