My first attempt at a guide. Hope it's helpful:
Sometimes the best way to use a Great General can be difficult to determine. Do I want to be able to produce better units in one city, build units faster in one city, or do I want one super powerful and super cool unit? First, the basics:
A. How are Great Generals produced?
B. What can a Great General be used for?
C. The main issue: Experience of Units and Promotions.
D. What good is a warlord unit?
E. How many Great Instructors do I settle, and when?
F. A brief word on Military Academies:
Like most aspects of this game, the optimal use of a Great General is very situational, but I hope the tips I provided above will help you crush your enemies, and hear the lamentations of their women, as Conan would say.
Sometimes the best way to use a Great General can be difficult to determine. Do I want to be able to produce better units in one city, build units faster in one city, or do I want one super powerful and super cool unit? First, the basics:
A. How are Great Generals produced?
Spoiler :
It should first be noted that barbarian kills do not count. When one of your units gains experience from a battle with another civilization, those points go not only towards the unit but also towards generating a Great General. In order to gain exp, your unit must win or withdraw, but if that unit dies it does not affect Great General points. Riskier battles generate more experience and Great General points when you win, except in the case of attacking siege units.
The Great General can be born in any of your cities, and can be born in the middle of the turn if you fill up the Great General bar while attacking. It will be born at the beginning if you do so while defending. The Great General bar can be seen on the military advisor screen.
Like other great people, it takes more and more points as you get more Great Generals, though it operates independently of other great people points because it is based upon total non-barbarian experience.
Other points include that Imperialistic leaders will require half as much exp to produce each Great General, and that the Great Wall also double the emergence of Great Generals for battles within your cultural borders. Thus, an Imperialistic leader will receive 4X credit towards getting a Great General if he/she has the Great Wall and wins a battle within cultural borders.
The Great General can be born in any of your cities, and can be born in the middle of the turn if you fill up the Great General bar while attacking. It will be born at the beginning if you do so while defending. The Great General bar can be seen on the military advisor screen.
Like other great people, it takes more and more points as you get more Great Generals, though it operates independently of other great people points because it is based upon total non-barbarian experience.
Other points include that Imperialistic leaders will require half as much exp to produce each Great General, and that the Great Wall also double the emergence of Great Generals for battles within your cultural borders. Thus, an Imperialistic leader will receive 4X credit towards getting a Great General if he/she has the Great Wall and wins a battle within cultural borders.
B. What can a Great General be used for?
Spoiler :
1. Attach to a unit, giving that unit the “led by warlord” promotion as well as 20 exp points divided evenly among units in the tile.
2. Settle as a Great Instructor in a city, yielding 2 extra exp points for all military units produced in that city.
3. Build a Military Academy (requires Military Science), giving a 50% production bonus when building military units.
2. Settle as a Great Instructor in a city, yielding 2 extra exp points for all military units produced in that city.
3. Build a Military Academy (requires Military Science), giving a 50% production bonus when building military units.
C. The main issue: Experience of Units and Promotions.
Spoiler :
1. Experience per promotion: Units gain promotions following the equation Exp=n^2+1 where n is number of promotions. So we normally get them at 2, 5, 10, 17, 26, 37, 50, 65, 82, 101, etc. Charismatic leaders follow the equation Exp=0.75(n^2+1) rounded up, so we get 2, 4, 8, 13, 20, 28, 38, 49, 62, 76.
2. Experience reset: Regular units with more than 10 experience points will have their experience reset to 10 upon upgrade. They keep their promotions, but will need to gain a large amount of exp to gain further promotions. For example, a knight with 26 exp uses its last promotions and is upgraded to a cavalry. In order for the cavalry to gain another promotion, it will need to get to 37 exp from 10 before it dies or is upgraded to a gunship. Having a warlord attached to a unit negates this problem for that unit only. Experience will not reset upon upgrade for a warlord-led unit.
2. Experience reset: Regular units with more than 10 experience points will have their experience reset to 10 upon upgrade. They keep their promotions, but will need to gain a large amount of exp to gain further promotions. For example, a knight with 26 exp uses its last promotions and is upgraded to a cavalry. In order for the cavalry to gain another promotion, it will need to get to 37 exp from 10 before it dies or is upgraded to a gunship. Having a warlord attached to a unit negates this problem for that unit only. Experience will not reset upon upgrade for a warlord-led unit.
D. What good is a warlord unit?
Spoiler :
In order to understand the next section, this needs to be addressed first. Warlords are fun and powerful, but they are just one unit. Typically the AI will settle Great Generals or build academies if available, which is good for it because it’s not very effective at using warlords. You do sometimes see them use warlords if one is born in a city as it is being attacked. There are four significant advantages to warlords:
1. You don’t have to spend hundreds of gold over the course of the game to upgrade the unit as you get free upgrades.
2. The experience is not reset to 10 upon upgrade.
3. The unit has access to unique promotions including: Leadership (+100% experience from combat), Tactics (+30% withdrawal), Combat 6 (+25% strength, requires C5), Morale (+1 movement), Medic 3 (+15% healing of units in same tile and adjacent tiles, requires Medic 2).
4. Upon attaching the Great General, 20 experience points are evenly distributed among units in the tile.
Except in dire circumstances where survival is questionable, leadership should be the first promo given to a warlord unit. It is a short term investment but it will pay for itself in terms of getting the unit more promotions in the long run. Delaying leadership will reduce the returns it gives. Leadership does not, however, increase great general emergence as one might expect. The great general bar fills the same as it would have if the unit did not have leadership, as popejubal pointed out.
Attach the warlord with only a few units that need the experience, or just the one you’re attaching it to. Diluting the 20 exp among 20+ units is not usually ideal. Every unit in the stack when you attach the warlord unit should be there to get a promotion from the 20 exp. If there are 4 units, each will get 5 exp, and each should need about that much for its next promotion. For uneven numbers, expect the extra one not to go to the warlord unit.
Attaching with multiple units is often a good idea if the unit that is becoming the warlord is already a great unit and is just picking up leadership or medic 3. Another option is to find a warrior or archer somewhere in the interior of your empire and give it all 20 exp, upgrading it an advanced unit. It’s a very cost effective way of adding a good unit to your stack. I’d recommend trying it as a charismatic leader, since they conveniently get their 5th promo at 20 points.
You'll want your wardlord unit to offer advantages your other units cannot offer due to the unique promotions available to it. This causes a tendency for there to be three basic types of warlord units: Sheer strength, withdrawer, and supermedic.
1. Sheer strength: The combat promotions work best on units with a high base strength, particularly ones that receive defensive bonuses. An advanced city raider that already has a toe on the combat line has proven potent in my games. CR1, CR2, CR3, Combat1, C2, attach warlord, Leadership, C3, C4, C5, C6, pinch, etc. And now you have a unit that is incredibly powerful versus cities, but also a good defender. Other good examples have been privateer -> destroyer, battleships, etc. With blitz, a naval warlord can single-handedly destroy a fleet of inferior tech.
2. Withdrawer: For any unit with a base withdrawal chance, this is a good way to go. Cavalry were made for this. Their base withdrawal is 30% so we have flanking I, flanking II, tactics, leadership as the initial promotions. This allows the unit to reach the withdrawal cap of 90%. The unit may allow you to not need to sacrifice siege as often, saving hammers at some risk to the warlord. The challenge of using this unit is determining acceptable risk for a given battle. If you have a 30% chance of winning, you’ll have a 93% chance of either winning or withdrawing. But within 9 battles at those odds you'll lose the unit 48% of the time (0.93^9 = 0.52). Put differently, the unit will survive an average of 13.28 battles according to P/(1-P). The full explanation for this is in the 6th post of this thread by PieceOfMind.
If you have an 80% chance of winning, your unit will have an 18% chance of withdrawal, making the odds of a positive outcome 98%, which is acceptable IMO.
What makes this especially good is that you can make huge leaps in experience without huge risk. If you win at 80%, leadership will cause you to gain 4 exp. The high withdrawal rate (but not leadership) will help you generate another great general at low risk as well. If you withdraw, you’ll still gain 2 exp from leadership. It will survive 34 battles at these 98% odds of a favorable outcome about 50% of the time (0.98^34=0.5). On average the unit will win 49 battles before death. The downside, of course, is that once your enemy has rifles you will not have odds like that as often, and gunships are a long way away. You can still farm Great General points and promotions by attacking weakened units, but then the unit isn't doing anything critical for your army in the short term.
Once you pass combat 3 and have military science, you’ll also want to put blitz on this unit. This will synergize with leadership and 90% withdrawal to make further ridiculous gains in exp. More importantly, it will make an awesome gunship later. Gunships are a little worse at withdrawing (25% base instead of 30%, for a maximum of 85% with flanking 2 and tactics), but can attack up to 5 times per turn with the morale promotion. With Blitz, that means you can totally slaughter an opponent lagging in tech.
Guerilla units are another possibility for a withdrawal unit, particularly if you’re Celtic with the free guerilla I from duns. With guerilla 3 and tactics, the unit can achieve 80% withdrawal.
Horse archers also can achieve 80% withdrawal, but it’s generally inadvisable unless you’re Arabic, given that knights, with the exception of camel archers, do not have a base withdrawal chance and so the unit will be pretty worthless during the middle ages.
Finally there’s the attack submarine. Their base withdrawal is 50%, very high. As DanF5771 pointed out in another thread, the game will not allow you to add a promotion that will put the withdrawal chance above 90%. However, he also noted that you can attach a Great General to a caravel, give it flanking1+2 and tactics, and then upgrade it to an attack submarine that has “110%” withdrawal, i.e. 100%. Unfortunately, the unit becomes unable to get further promotions after that due to some glitch. It may still be worth doing it, but generally a regular flanking 2 attack sub with 80% withdrawal is good enough to not use a Great General on it.
3. Supermedic: A popular use of the Great General is to create a super medic that can heal units in the same and adjacent tiles 25%, or even combining woodsman 3 with medic 3, for +40% healing in the same tile. This can be done with a melee or gunpowder unit – other units don’t get woodsman 3.
The disadvantage of using a warlord as a medic is that a non-warlord healer can do a respectable job. A woodsman 3 healer can be produced from one or more of your original warriors. Early in warmongering, +15% healing is often adequate. The woodsman promo will cause it to defend when your stack is in forests, allowing you to reach further promotions. It can also attack units that don't receive defensive bonuses while they're in forests. It’s relatively easy to then reach a medic I unit, giving 25% healing, which is as good as a non-woodsman super medic. 40% can be overkill, though there is some synergy between this medic and a withdrawal warlord. When the withdrawal warlord withdraws, it’ll be at very low health. A 40% medic will make him useable without delay.
The utility of the uber supermedic unit seems to be dependent upon several factors such as game speed, i.e. 40% healing instead of 25% might be more critical on quick than marathon. It is more useful when barbarians are turned off, as that makes it more difficult to get woodsman 3 units, or when you’re not playing an aggressive or charismatic leader, as that makes the non-warlord 25% healer less easily attainable.
1. You don’t have to spend hundreds of gold over the course of the game to upgrade the unit as you get free upgrades.
2. The experience is not reset to 10 upon upgrade.
3. The unit has access to unique promotions including: Leadership (+100% experience from combat), Tactics (+30% withdrawal), Combat 6 (+25% strength, requires C5), Morale (+1 movement), Medic 3 (+15% healing of units in same tile and adjacent tiles, requires Medic 2).
4. Upon attaching the Great General, 20 experience points are evenly distributed among units in the tile.
Except in dire circumstances where survival is questionable, leadership should be the first promo given to a warlord unit. It is a short term investment but it will pay for itself in terms of getting the unit more promotions in the long run. Delaying leadership will reduce the returns it gives. Leadership does not, however, increase great general emergence as one might expect. The great general bar fills the same as it would have if the unit did not have leadership, as popejubal pointed out.
Attach the warlord with only a few units that need the experience, or just the one you’re attaching it to. Diluting the 20 exp among 20+ units is not usually ideal. Every unit in the stack when you attach the warlord unit should be there to get a promotion from the 20 exp. If there are 4 units, each will get 5 exp, and each should need about that much for its next promotion. For uneven numbers, expect the extra one not to go to the warlord unit.
Attaching with multiple units is often a good idea if the unit that is becoming the warlord is already a great unit and is just picking up leadership or medic 3. Another option is to find a warrior or archer somewhere in the interior of your empire and give it all 20 exp, upgrading it an advanced unit. It’s a very cost effective way of adding a good unit to your stack. I’d recommend trying it as a charismatic leader, since they conveniently get their 5th promo at 20 points.
You'll want your wardlord unit to offer advantages your other units cannot offer due to the unique promotions available to it. This causes a tendency for there to be three basic types of warlord units: Sheer strength, withdrawer, and supermedic.
1. Sheer strength: The combat promotions work best on units with a high base strength, particularly ones that receive defensive bonuses. An advanced city raider that already has a toe on the combat line has proven potent in my games. CR1, CR2, CR3, Combat1, C2, attach warlord, Leadership, C3, C4, C5, C6, pinch, etc. And now you have a unit that is incredibly powerful versus cities, but also a good defender. Other good examples have been privateer -> destroyer, battleships, etc. With blitz, a naval warlord can single-handedly destroy a fleet of inferior tech.
2. Withdrawer: For any unit with a base withdrawal chance, this is a good way to go. Cavalry were made for this. Their base withdrawal is 30% so we have flanking I, flanking II, tactics, leadership as the initial promotions. This allows the unit to reach the withdrawal cap of 90%. The unit may allow you to not need to sacrifice siege as often, saving hammers at some risk to the warlord. The challenge of using this unit is determining acceptable risk for a given battle. If you have a 30% chance of winning, you’ll have a 93% chance of either winning or withdrawing. But within 9 battles at those odds you'll lose the unit 48% of the time (0.93^9 = 0.52). Put differently, the unit will survive an average of 13.28 battles according to P/(1-P). The full explanation for this is in the 6th post of this thread by PieceOfMind.
If you have an 80% chance of winning, your unit will have an 18% chance of withdrawal, making the odds of a positive outcome 98%, which is acceptable IMO.
What makes this especially good is that you can make huge leaps in experience without huge risk. If you win at 80%, leadership will cause you to gain 4 exp. The high withdrawal rate (but not leadership) will help you generate another great general at low risk as well. If you withdraw, you’ll still gain 2 exp from leadership. It will survive 34 battles at these 98% odds of a favorable outcome about 50% of the time (0.98^34=0.5). On average the unit will win 49 battles before death. The downside, of course, is that once your enemy has rifles you will not have odds like that as often, and gunships are a long way away. You can still farm Great General points and promotions by attacking weakened units, but then the unit isn't doing anything critical for your army in the short term.
Once you pass combat 3 and have military science, you’ll also want to put blitz on this unit. This will synergize with leadership and 90% withdrawal to make further ridiculous gains in exp. More importantly, it will make an awesome gunship later. Gunships are a little worse at withdrawing (25% base instead of 30%, for a maximum of 85% with flanking 2 and tactics), but can attack up to 5 times per turn with the morale promotion. With Blitz, that means you can totally slaughter an opponent lagging in tech.
Guerilla units are another possibility for a withdrawal unit, particularly if you’re Celtic with the free guerilla I from duns. With guerilla 3 and tactics, the unit can achieve 80% withdrawal.
Horse archers also can achieve 80% withdrawal, but it’s generally inadvisable unless you’re Arabic, given that knights, with the exception of camel archers, do not have a base withdrawal chance and so the unit will be pretty worthless during the middle ages.
Finally there’s the attack submarine. Their base withdrawal is 50%, very high. As DanF5771 pointed out in another thread, the game will not allow you to add a promotion that will put the withdrawal chance above 90%. However, he also noted that you can attach a Great General to a caravel, give it flanking1+2 and tactics, and then upgrade it to an attack submarine that has “110%” withdrawal, i.e. 100%. Unfortunately, the unit becomes unable to get further promotions after that due to some glitch. It may still be worth doing it, but generally a regular flanking 2 attack sub with 80% withdrawal is good enough to not use a Great General on it.
3. Supermedic: A popular use of the Great General is to create a super medic that can heal units in the same and adjacent tiles 25%, or even combining woodsman 3 with medic 3, for +40% healing in the same tile. This can be done with a melee or gunpowder unit – other units don’t get woodsman 3.
The disadvantage of using a warlord as a medic is that a non-warlord healer can do a respectable job. A woodsman 3 healer can be produced from one or more of your original warriors. Early in warmongering, +15% healing is often adequate. The woodsman promo will cause it to defend when your stack is in forests, allowing you to reach further promotions. It can also attack units that don't receive defensive bonuses while they're in forests. It’s relatively easy to then reach a medic I unit, giving 25% healing, which is as good as a non-woodsman super medic. 40% can be overkill, though there is some synergy between this medic and a withdrawal warlord. When the withdrawal warlord withdraws, it’ll be at very low health. A 40% medic will make him useable without delay.
The utility of the uber supermedic unit seems to be dependent upon several factors such as game speed, i.e. 40% healing instead of 25% might be more critical on quick than marathon. It is more useful when barbarians are turned off, as that makes it more difficult to get woodsman 3 units, or when you’re not playing an aggressive or charismatic leader, as that makes the non-warlord 25% healer less easily attainable.
E. How many Great Instructors do I settle, and when?
Spoiler :
A problem with relying on warlords, with the possible exception of medics, is that the unit is risked in every round of combat. One can much more reliably prevent a core city from getting captured than a powerful unit from getting killed. A sheer strength warlord may be powerful enough to handle 2 or 3 units of equal tech, but that would make less of a difference than having your whole stack have an extra promotion. If your enemy’s stack is triple the size of yours, equal in tech, or siege-heavy, your warlord is not going to save you despite its coolness. It is also useful to know your enemy. Is my enemy going to have a small group of well-promoted, cutting-edge troops, or a huge number of poorly-promoted, low-tech troops? Usually the AI produces the latter, so settling is favored.
Withdrawer Warlords will increase further Great General production, but then the other units produced by your main military city will be weaker. In almost any situation, you’re going to want to settle your first Great General in a high production city, where you have or will build the heroic epic. The reason is that the +2 exp is going to make the biggest difference for most units. The second promotion comes at 4 (charismatic) or 5 experience, and your barracks provide 3. Hence the settled Great General will give each land unit a second promotion, and other types of units a first promotion by itself.
Economically, Great Instructors give units produced in that city a better chance of being effective or surviving, and therefore saving hammers. To get the most out of them, you’ll want the city with settled Instructors to be producing units most of the time. Hence settling Great Generals demands that you engage in city specialization. Your heroic epic city with the Great Generals won’t be building universities, observatories, and banks. It’ll be too busy building military units only stopping to build things like a forge, levee and factory. Its improvements won’t include cottages. But somewhere else, preferably in the interior of your empire, you’ll have cities with 10+ cottages that build things like universities and banks, but no barracks or stables, and will never build a military unit. This is especially important if you opt to use theocracy much, as you are giving up organized religion.
One General rule is to choose one city to settle your Great Generals unless you’re charismatic and plan on using vassalage and theocracy for most of the game, in which case you can build level 4 units in 2 cities with 1 settled Instructor each. Alternatively, charismatic makes it much more viable to make level 5 units (4 promos, 13 exp) with multiple settled Instructors in one city and/or civics/wonders.
Protective leaders in particular should settle their first Great General. Since they start with CG1, the one Great General will mean they can immediately produce CG3 units, or get to drill IV much more quickly. Other interesting scenarios would be with the Celts, where you can produce Guerilla 3 units due to the dun, and the Aztec Jaguar which can immediately be woodsman 3. Spain’s citadel, with +5 to siege, will allow the production of CR3 siege with a single settled Instructor as well.
A possible exception to settling the first GG would be if your army is based upon mounted units, as the stable will bring them to 5 experience and the Instructor will not bring them especially close to another promotion. However, combining the Ger with barracks and an Instructor will bring Mongolian mounted units one exp away from a 3rd promotion, which can be significant if we’re talking about elephants versus elephants, not to mention the keshik-based fast army.
My armies usually use mounted units, but not as the main component. So I use a secondary military city with a stable to build things like knights and some siege, and I don’t build a stable or mounted units in the main military city.
By the second Great General the choice becomes less obvious. The next promotion is 10 exp, so it takes 3 more settled Instructors to build units with a 3rd promotion. It only requires 2 more if your leader is charismatic (requires 8 exp). For that reason you should probably settle the 2nd and 3rd one if your leader is charismatic. Despite how amazing charismatic warlords can be, they’re still just one unit in the scheme of things.
Sometimes you’re about to research civil service and have a really advanced unit that will be simply amazing if you attach a Great General and you don’t want to halt the progress that unit has made with the experience reset. Alternatively, if you have the pyramids and are running representation, the Great Instructors bring in 3 beakers each. This adds up over time, but is only a minor consideration since that city won’t likely have time to build universities/ observatories.
Mid-game civics, including theocracy and vassalage, can give you another 4 exp. With a spiritual leader, one can settle the 2nd Great General, utilize both theocracy and vassalage, and then switch to one of the more economic civics when another Great General arrives. But all of this can be a big opportunity cost for not running civics like bureaucracy and organized religion. Vassalage has the benefit of decreasing unit costs.
In General, whether I settle the 2nd 3rd and 4th GG depends upon a few more factors.
1. If my capital is not my military city and is not especially strong commerce/production wise but is well-located and/or perfectly good acting as a GP farm or something, then vassalage makes more sense than bureaucracy. When using vassalage, it actually makes more sense to settle the second Great General because you can at least build units that are one point away from level 4.
2. Another, equally important question is whether it would be more useful to have more Great Generals over the course of the game or produce level 4 units sooner. For example, I really like to have CR3 maces. If I already have enough of those for 2 stacks from barbarians and warfare, then I don’t have an immediate need for level 4 units. Alternatively, if I’m using some other strategy, I might want more GG over the course of the game. If I only have enough surviving ones for one stack towards the end of medieval warfare, then settling Great Generals to produce another stack to upgrade to CR3 gunpowder makes sense.
3. Finally, what is the 2nd national wonder I’m going to build in my heroic epic city? Generally this is going to be West Point or Ironworks. I’m going to want to settle more GG in my heroic epic city if I’m not going to build West Point there later.
Example scenarios where I build Ironworks:
If I’m a warmonger and:
I capture an enemy city with significant production and one or more settled Instructors. These cities tend to cause me to build ironworks in the heroic epic city, so that this new city can become a secondary military city with west point.
Sometimes I feel I need a secondary military city that can produce high level units, as in when I’m on a non-pangea map but my heroic epic city is not on the coast. This second military city becomes my primary naval unit city, and secondary producer of land units.
Example scenario where I build West Point:
The above doesn’t happen or I’m not being a warmonger. If my eventual goal is a space race victory, for example, I’m going to want ironworks in a non-military production city and have only one city producing veteran units constantly at a lower level. I am also unlikely to get 4 Great Generals if I’m not waging a lot of war, so the extra experience from west point is more necessary.
When I am going to build ironworks in the heroic epic city, I tend to settle the first four Great Generals.
Withdrawer Warlords will increase further Great General production, but then the other units produced by your main military city will be weaker. In almost any situation, you’re going to want to settle your first Great General in a high production city, where you have or will build the heroic epic. The reason is that the +2 exp is going to make the biggest difference for most units. The second promotion comes at 4 (charismatic) or 5 experience, and your barracks provide 3. Hence the settled Great General will give each land unit a second promotion, and other types of units a first promotion by itself.
Economically, Great Instructors give units produced in that city a better chance of being effective or surviving, and therefore saving hammers. To get the most out of them, you’ll want the city with settled Instructors to be producing units most of the time. Hence settling Great Generals demands that you engage in city specialization. Your heroic epic city with the Great Generals won’t be building universities, observatories, and banks. It’ll be too busy building military units only stopping to build things like a forge, levee and factory. Its improvements won’t include cottages. But somewhere else, preferably in the interior of your empire, you’ll have cities with 10+ cottages that build things like universities and banks, but no barracks or stables, and will never build a military unit. This is especially important if you opt to use theocracy much, as you are giving up organized religion.
One General rule is to choose one city to settle your Great Generals unless you’re charismatic and plan on using vassalage and theocracy for most of the game, in which case you can build level 4 units in 2 cities with 1 settled Instructor each. Alternatively, charismatic makes it much more viable to make level 5 units (4 promos, 13 exp) with multiple settled Instructors in one city and/or civics/wonders.
Protective leaders in particular should settle their first Great General. Since they start with CG1, the one Great General will mean they can immediately produce CG3 units, or get to drill IV much more quickly. Other interesting scenarios would be with the Celts, where you can produce Guerilla 3 units due to the dun, and the Aztec Jaguar which can immediately be woodsman 3. Spain’s citadel, with +5 to siege, will allow the production of CR3 siege with a single settled Instructor as well.
A possible exception to settling the first GG would be if your army is based upon mounted units, as the stable will bring them to 5 experience and the Instructor will not bring them especially close to another promotion. However, combining the Ger with barracks and an Instructor will bring Mongolian mounted units one exp away from a 3rd promotion, which can be significant if we’re talking about elephants versus elephants, not to mention the keshik-based fast army.
My armies usually use mounted units, but not as the main component. So I use a secondary military city with a stable to build things like knights and some siege, and I don’t build a stable or mounted units in the main military city.
By the second Great General the choice becomes less obvious. The next promotion is 10 exp, so it takes 3 more settled Instructors to build units with a 3rd promotion. It only requires 2 more if your leader is charismatic (requires 8 exp). For that reason you should probably settle the 2nd and 3rd one if your leader is charismatic. Despite how amazing charismatic warlords can be, they’re still just one unit in the scheme of things.
Sometimes you’re about to research civil service and have a really advanced unit that will be simply amazing if you attach a Great General and you don’t want to halt the progress that unit has made with the experience reset. Alternatively, if you have the pyramids and are running representation, the Great Instructors bring in 3 beakers each. This adds up over time, but is only a minor consideration since that city won’t likely have time to build universities/ observatories.
Mid-game civics, including theocracy and vassalage, can give you another 4 exp. With a spiritual leader, one can settle the 2nd Great General, utilize both theocracy and vassalage, and then switch to one of the more economic civics when another Great General arrives. But all of this can be a big opportunity cost for not running civics like bureaucracy and organized religion. Vassalage has the benefit of decreasing unit costs.
In General, whether I settle the 2nd 3rd and 4th GG depends upon a few more factors.
1. If my capital is not my military city and is not especially strong commerce/production wise but is well-located and/or perfectly good acting as a GP farm or something, then vassalage makes more sense than bureaucracy. When using vassalage, it actually makes more sense to settle the second Great General because you can at least build units that are one point away from level 4.
2. Another, equally important question is whether it would be more useful to have more Great Generals over the course of the game or produce level 4 units sooner. For example, I really like to have CR3 maces. If I already have enough of those for 2 stacks from barbarians and warfare, then I don’t have an immediate need for level 4 units. Alternatively, if I’m using some other strategy, I might want more GG over the course of the game. If I only have enough surviving ones for one stack towards the end of medieval warfare, then settling Great Generals to produce another stack to upgrade to CR3 gunpowder makes sense.
3. Finally, what is the 2nd national wonder I’m going to build in my heroic epic city? Generally this is going to be West Point or Ironworks. I’m going to want to settle more GG in my heroic epic city if I’m not going to build West Point there later.
Example scenarios where I build Ironworks:
If I’m a warmonger and:
I capture an enemy city with significant production and one or more settled Instructors. These cities tend to cause me to build ironworks in the heroic epic city, so that this new city can become a secondary military city with west point.
Sometimes I feel I need a secondary military city that can produce high level units, as in when I’m on a non-pangea map but my heroic epic city is not on the coast. This second military city becomes my primary naval unit city, and secondary producer of land units.
Example scenario where I build West Point:
The above doesn’t happen or I’m not being a warmonger. If my eventual goal is a space race victory, for example, I’m going to want ironworks in a non-military production city and have only one city producing veteran units constantly at a lower level. I am also unlikely to get 4 Great Generals if I’m not waging a lot of war, so the extra experience from west point is more necessary.
When I am going to build ironworks in the heroic epic city, I tend to settle the first four Great Generals.
F. A brief word on Military Academies:
Spoiler :
I would not build these outside of a city that has West Point and/or settled Instructors. As of 3.17 these actually do require Military Science to be built, and so come relatively late. If your military city is already producing a unit every turn or even a unit every other turn on marathon, it would usually be better to use the Great General for something else. Calculate if the military academy would make a turn difference in producing units without overflow in either your primary or a secondary military city. Then if settling another Instructor won’t get you another promotion, and if there is no awesome unit to attach a warlord too, then build the military academy in the appropriate city.
Like most aspects of this game, the optimal use of a Great General is very situational, but I hope the tips I provided above will help you crush your enemies, and hear the lamentations of their women, as Conan would say.
Don't worry I'm very familiar with the term - I'm trained as a mathematician, which is why I tend to be pedantic about the way the term is used. Infinity is like a dirty word to mathematicians (as is infinitesimal, to a lesser extent). People like physicists love the words though and use them much more liberally, because they need not be concerned with mathematical rigour, only practical results.
(kittens, here, obviously meaning all kinds of kittens, and we all know tigers are the most awesome of kittens)
