aelf
Ashen One
While the War Academy teaches specific strategies involving extensive use of the prominent UUs, there isn't a guide to explain the uses of the others. Strong ones like the Praetorian often need no introduction, but many players are not exposed to the possibilities that the more subtle ones present.
I hope this guide would help you leverage the different UUs effectively or at least inspire you to be more creative with them. Give all of them a chance! But please note that this guide is written mainly for single player games. Some tips may still be useful for multiplayer, but I can't promise that. This guide also assumes that you are playing as leaders under the normal civs.
Thanks to Robo Kai, kniteowl, Cabert, Wodan, johnny_rico, gusi, UncleJJ, Bjorn190, dime, s.c.dude, drkodos, kristopherb, Elandal, Thyrwyn, Phrederick, Polycrates, Thedrin, agc28, PraetorianSteve, svv, carl corey, Andrei_V, Mr. Civtastic, Thomas G., GeneralGab, Percy, r_rolo1, facistal, jason77024, GoliathFF8 and InvisibleStalke for ideas and contributions that helped make this guide possible.
The different UUs are listed under their civs, in alphabetical order. Note: Due to the additional UUs and changes in BTS, this guide is currently still work-in-progress. So don't be surprised if you don't see an entry for a UU or a relevant BTS note. Feel free to give some advice on the UUs that have not been touched on or on any new tips or tricks for existing UUs. Your suggestions will be appreciated.
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America: Navy SEAL (Marine)
Once you've gotten over the fact that it comes very late in the game, you might realise that the Navy SEAL is actually good UU. A marine replacement, it might seem to be a niche unit. After all, how often do you conduct amphibious attacks (which include those across a river, by the way)? But take a closer look at its unique advantages and you'll realise the potential it has.
Its first strike and first strike chances are not to be taken lightly. First strikes can help you deal more damage to the enemy and comfortably win battles that you might otherwise take heavy damage in or even lose. The free March promotion, meanwhile, allows the Navy SEAL to heal on the go, reducing the time it takes to recover before heading off to another battle. Bringing a Medic III unit along with your SEALs means that as soon as they have attacked, they are eligible for the 30% healing the next turn (5% from enemy territory and 25% from Medic III). So as long as they are at or above 16.8/24 strength, they will be back to full health the next turn. They can also heal right after making an amphibious assault aboard a Medic transport. The SEALs in Civ4 are indeed an elite task force worthy of their name, capable of enduring and sustaining a long campaign.
The 50% attack bonuses against machine guns and artillery are a thick layer of icing on the cake. With SEALs, you don't have to fret when attacking cities defended by machine guns (which are immune to collateral damage) without tanks. Their first strikes also help by negating the machine gun's first strikes. And, also due to their first strikes, SEALs are probably the best stack protectors against enemy artillery attacks. Divide your stack(s) into smaller SEAL-protected groups and you don't have to worry too much about getting overwhelmed by mass artillery.
Whether you have some coastal cities to assault or a land campaign to conduct, Navy SEALs are an excellent unit to bring along with your invasion force. They do come late, but they come at the right time if you're planning on a late domination push that would win you the game.
For BTS players: Gunpowder units can now be given Drill promotions, and the Navy SEAL certainly benefits from this. Besides getting more first strikes and first strike chances, which increase its survivability even more, it also gets up to 60% protection from collateral damage to help against those artillery attacks. Hence, Drill should be the promotion for many, if not most, Navy SEALs.
Arabia: Camel Archer (Knight)
Camel Archers are knights that have a higher withdrawal chance (25%) and don't require horses or iron. You could simply use them like normal knights, but the thing about them is Flanking promotions make them very good at surviving failed attacks (+55% withdrawal chance with Flanking II). This means you don't have to balk so much at attacking a city or a stack that has a defending pike, making them more reliable as an attack unit. Of course, if you end up with no horses or iron, they give you the option of building knights in the first place.
If you're playing on Warlords, stables can give your Camel Archers enough experience points to start off with Flanking I and II, so you don't have to be running Vassalage or Theocracy. Also, you can improve their ability even further by attaching Great Generals to them as warlords. Give a Flanking II Camel Archer the Tactics promotion (+30% withdrawal chance) and it would have 85% chance of retreating from a failed attack. Of course, you might still get unlucky and lose it, especially if you attack at very low odds. It's not 100% withdrawal chance, you know.
Aztecs: Jaguar Warrior (Swordsman)
Traditional whipping boys, these guys get 2 free promotions in Warlords, Woodsman I and Combat I (the latter thanks to Montezuma's Aggressive trait). If you've built those cheap barracks, giving them Woodsman II immediately would allow you to rush a relatively cheap stack of them (Jaguars cost less than normal swordsmen) to enemy cities through forests and jungles, in which they have two moves. Of course, this comes at the price of not being able to give them the City Raider promotion first, but depending on how fortified the target cities are, this may not be such a problem. Jaguars do get the swordsman's inherent 10% bonus when attacking cities.
On a more conventional level, the benefit of the Jaguar is probably similar to that of the Gallic Warrior - better stack protection when standing on a particular terrain. Jaguars can even defend against axemen when positioned in forests and jungles, as they get 70% terrain defense bonus there (+50% from the terrain and +20% from Woodsman I), making them good all-round defenders in this situation. Give them Woodsman II or Shock (both available immediately with barracks) and they would have no need to be afraid of axemen as long as they have trees to cover them. Hence, if the enemy's lands sport plenty of foliage, you may want to bring a few of them along in any case. Note that this applies only to jungles in Civ4 vanilla, where Jaguars get 75% defense bonus (+50% from the terrain and +25% jungle defense bonus).
Jaguars don't require any resource so you can start building them even before hooking up copper or iron. You can also whip them out (probably with unhappy citizens) in newly conquered cities that are not connected to any metal resource, immediately creating some units for either garrison or further offensive purposes and thus helping you proceed with your campaign without having to wait for reinforcements. The value of this UU greatly increases when you find yourself without copper and iron in the first place.
More on the no resource requirement, Jaguars are a sure way to rush a neighbour early in the game. You can plant your second city on the best production site in the direction of your target without waiting for copper or iron to be revealed. Then you build barracks and granary, research IW and start whipping Jaguars out without even having to bother with any resources. Get a stack of them and attack Aztec-style.
For BTS players: With the addition of the Woodsman III promotion, Jaguars have become much more useful in an interesting way. Woodsman III grants 2 first strikes, +50% forest and jungle attack and the ability to heal units on the same tile at the rate of 15% per turn. Since Jaguars get Woodsman I for free and barracks can give them Woodsman II off the bat, they are effectively 2 XP away from becoming the ultimate forest/jungle warriors of their time and effective medics. If you need to take out some enemy units that are fortified in a forest/jungle, especially those that are there to choke your cities, unleash the Woodsman III Jaguars. If you need some quick healing, you have Woodsman III Jaguars. A very handy support unit to have around for early warfare. They are probably still not such effective combat units on their own, but the first strikes might help.
You can even maximise the Jaguar's healing ability by attaching a Great General to it and giving it all three Medic promotions as well. Woodsman III's healing stacks with the Medic promotions (provided they are on the same unit), giving you a whooping 50% healing rate. And this isn't difficult to achieve since Jaguars get free Combat I (required for Medic I) thanks to Aggressive, so you only need 26 XP to get there. Attaching a Great General to a unit gives you 20 XP, so that Jaguar effectively only needs 6 XP, the first 3 of which can be given by barracks.
Carthage: Numidian Cavalry (Horse Archer)
Warlords and BTS only. This is a UU that people are divided about. Some regard it as a good UU (though not great). Others think it is weak. The latter opinion can usually be attributed to the traditional aversion to horse archers, Horseback Riding (HBR) and Archery (techs required to build horse archer-type units). Horse archers have two moves and are good for busting archer-defended cities, but they die to spearmen, rendering them easy to counter. Archery is widely viewed as a useless dead end tech early on, while HBR is fairly expensive, making it tempting to research other more beneficial techs first. The latter's beaker cost also makes it difficult to ensure that your opponents don't have spears yet by the time it's researched. Add the fact that horse archers suffer from a 10% penalty when attacking cities in Warlords, and that the Numidian Cavalry is 1 strength weaker than normal horse archers, it's easy to turn your back on the Carthaginian UU.
However, if you consider it carefully, you may find that it's actually worth something depending on the situation. In Warlords, HBR allows you to build stables (+2 exp to mounted units), which would give your horses an edge in promotions before Vassalage/Theocracy, making the tech more attractive to research early. And the Numidian Cavalry starts with Flanking I, so, with stables, you can give them Flanking II and another promotion (eg. Mobility) right off the bat. This would give them a 50% (20% natural ability + 30% from Flanking I and II) chance to withdraw from losing battles and, if you choose Mobility, the ability to more very quickly even in enemy territory. With the Charismatic trait, it's easy to get your Numidian Cavalry to the next level for yet another promotion. Don't forget that the free Flanking I would not disappear when you upgrade them to knights.
Those are not all. The Numidian Cavalry also gets 50% bonus vs. melee, as well as the 50% bonus vs. siege that horse archers have, making it virtually an improved axeman. It has no need to be overly afraid of spearmen, thanks to the melee bonus. And you can rely on Flanking II to increase the survival rate of your Numidian Cavalry when up against spears, or you can even the odds with Combat I and Shock. If there's no heavy cultural defense, Numidian Cavalry can do a decent job busting cities on their own, although you'll need a good number of them. As active empire defenders or counter units, they are versatile enough, having bonuses against two categories of units. As pillagers, they are excellent since spears, the easiest counter, are not as effective against them - just be sure to build stables and give them Combat I and Shock (of course, you may want a few Sentries). It may seem like a waste of their free Flanking I, but this way the enemy cannot easily drive your pillaging Numidians out. The few Flanking-promoted ones can attack enemy units guarding key resources. Remember to pillage ivory and horses first, since elephants and horse archers are the most effective counters to your UU.
The cons of the Numidian Cavalry are their reduced strength, the 10% penalty against cities and the fact that they can't get City Raider promotions. Once there's significant cultural defense in an enemy city, expect to take huge losses if you don't bring siege weapons along. Even if there's no cultural defense and the city is not on a hill, Numidian Cavalry are actually not as strong as the city's unpromoted fortified archers, so you need to bring at least twice as many. You can beeline to HBR and rush a neighbour with a moderate stack of them to quickly capture a few cities, but don't expect them to carve out a large empire for you.
For BTS players: Horse archers no longer get the 10% city attack penalty, so the Numidian Archer is slightly stronger now. It also gains mounted units' flanking attack ability (not to be confused with Flanking promotion), whereby it does 'collateral damage' to siege units in the stack it is attacking, making it better at countering mass catapults than before. These changes certainly mean that Carthage players have something to cheer about.
Celtia: Gallic Warrior (Swordsman)
Warlords and BTS only. The Gallic Warrior is a much-maligned UU. Most people wonder why an offensive unit is given a promotion for hill defense. How on earth is that going to help him attack cities, which is what it does best?
Attacking a city is the culmination of an offensive movement, which begins with your entering enemy territory. If you're careful, you would want to move your stack along the safest route to the target city as far as possible, which often means favouring forests and hills over flatlands. This is where the Gallic Warrior's free Guerilla I can help. While spearmen protect your stack against mounted units and axemen/crossbows protect it from melee units, a Gallic Warrior on a hill is the best defender against counterattacking catapults and can even take over the role of the other stack-protection units. For example, if your spearman is badly injured, the Gallic Warrior can defend against chariots or horse archers as long as you're on a hill. Thus, while normal swordsmen may be badly injured before reaching the target city in these circumstances, chances are Gallic Warriors would be in better shape.
And note that Gallic Warriors can be promoted with Guerilla II and III. Such units can be a thorn in your enemy's side, running through the hills pillaging mines and maybe raiding a weakly defended city or two, thanks to Guerilla III's movement bonus on hills. The 25% bonus for attacks on hills and 30% withdrawal chance that this promotion gives also make it easier for you to deal with stubborn hill cities. And now that you can build Gallic Warriors with copper in the latest versions of Warlords, this UU can make an extra early appearance for city-busting.
Another neat thing about this UU is the fact that you can upgrade it to more advanced units in its line without losing the free Guerilla I. So, in effect, the benefit of this UU lasts for a long time. Remember that forests can be chopped but hills are permanent.
For BTS players: Somewhat like the Jaguar, this UU benefits from an improvement to its natural promotion branch: the change to Guerrilla III. It still gives +25% hills attack but now it gives a 50% withdrawal chance, making a Guerilla III Gallic Warrior a very effective crack troop. Need to attack that fortified hilltop city before Construction? Guerilla III Gallic Warriors can soften the defenses and have a good chance of surviving even after losing. The 50% withdrawal chance really is quite amazing, outclassing both the Flanking promotions combined. Moreover, since both Celt leaders are Charismatic, it's really easy to get to Guerrilla III. With barracks, your Gallic Warriors can start with Guerilla II and you are only 1XP away from Guerilla III. Sounds like fun.
China: Chukonu (Crossbowman)
The Chukonu has a fearsome reputation. Collateral damage is something well-loved by most Civ4 players, and a respectable non-siege ground unit that has the ability to inflict it would surely become the favourite of some. The biggest weakness of siege units is their inability to defend effectively. The Chukonu, however, can function as an improved crossbowman, thus having an important benefit of siege units without the drawback.
You may find it hard to pinpoint the exact role of this UU, though. Crossbows are primarily a counter unit, designed to help eliminate the threat of enemy melee units, and can in turn be countered by mounted units. If the enemy builds stacks of melee, your Chukonus will tear them apart with their bonus vs melee, first strikes and collateral damage. If the enemy mixes his stacks with mounted units, Chukonus are less effective. Thanks to collateral damage and the extra first strikes, however, they are much less helpless than normal crossbows and are still able to attack such mixed stacks, although you would probably sustain losses initially. The idea is to wear the enemy units down with your extra hits and collateral damage. Given enough Chukonus, there's almost nothing you can't defeat in the field (assuming you are facing units of the same era). But the question arises: Are they more cost effective for this purpose than catapults, since the latter are cheaper? If the enemy only has melee units then the answer is clearly yes. If the enemy has mounted units (which may be immune to first strikes) in his stack, sending in a few scuicide catapults first would probably be a better idea. The Chukonus can do semi-cleanup, dealing even more collateral damage to the enemy units and making them extremely weak and easy for more Chukonus or other units to take out.
You can apply the same concept when attacking a city. Siege units are still needed to remove the city's defenses, but who does the first few assaults would depend on what sort of units are defending the city. If they are macemen and pikemen/spearmen, use your Chukonus. If there are archery/mounted units in the city, use the siege units first, followed by the Chukonus and finally the cleanup crew (if you have any). Remember, Chukonus don't get City Raider promotions, so be prepared to lose some as they attack at lower odds than your CR units might have.
The Chukonu's first strikes are useful on the offense, but they become the primary advantage on the defense. When Chukonus are defending, they won't get to inflict any collateral damage on the enemy units, but their first strikes would be a great boost. First strikes grant chances of hitting the enemy unit before the combat proper even begins, thus improving your odds. The stronger your unit is compared to the enemy's the better first strikes are, since the hits you score would do more damage, thus increasing the possibility of your unit winning without taking much damage. This makes them even better a defense against enemy melee units than normal crossbows. Their first strikes also work well when defending against siege weapons, since they might be able to win before much collateral damage is suffered.
Whether you give your Chukonus Drill promotions for more first strikes is up to you. Note that this UU has higher chances of being promoted than normal crossbowmen, since they are more suitable for an offensive role, making it possible to accumulate quite a few Drill promotions and a lot first strikes. Moreover, if you're playing on Warlords, both Chinese leaders are Protective, so Chukonus start with Drill I, giving you a headstart in that line of promotions. Gunpowder units can't choose Drill, so upgraded Chukonus can be interesting. Incidentally, Protective also makes the Chukonu better at defending cities, thanks to the free City Garrison I promotion.
On a final note, here's a tip on how to get Chukonus early and really overrun your neighbours: Choose Qin Shi Huang as your leader and aim to build the Oracle to grab Metal Casting (requires Pottery and Bronze Working). The Industrious trait makes getting the Oracle viable, even without marble. Metal Casting leads to Machinery, but it also allows you to build your cheap Industrious forges. Build one asap and run an engineer specialist. When a Great Engineer is born, use him to lightbulb Machinery, giving you access to the Chinese UU very early. But do note that Machinery requires Iron Working and Chukonus need the iron resource to be built, so make sure you get this tech researched while waiting for the GE to be born. The worst scenario is finding no iron in your territory. To help prevent this situation, research Iron Working as quickly as possible to locate iron resources and claim them if necessary.
Egypt: War Chariot (Chariot)
At 5 strength, the Egyptian War Chariot is essentially an axeman on wheels with no City Raider promotions but has withdrawal chance. It is a very powerful and mobile unit that can win your game from as early as the Ancient Era.
An Egyptian player who does not have copper has less to worry about. In fact, horses are much more important for him/her, making Animal Husbandry (AH) a priority. And since Egypt starts with Agriculture, which leads to AH, things are pretty much set up for you. Egypt also starts with The Wheel, which is required to build chariots and roads (to hook up those horses). What serendipity! Feel free to delay Bronze Working till you wish to use Slavery, unless it turns out that there are no horses within reasonable distance. If you discover horses nearby, get a settler there as soon as possible and hook it up. You can then begin preparing for your offensive. Chariot rushing has never been so effective.
While the chariot rush tactic of pillaging the enemy's metal mines should still be applied, War Chariots aren't as afraid of spears as normal chariots because of their increased strength. Additionally, you can give them the Shock promotion to help deal with enemy spears that you might encounter. This would also help vanilla players who face enemy axemen, since the chariot bonus vs. axes applies only after Warlords (vanilla players are somewhat compensated by having 20% withdrawal chance instead of just 10%, though). That said, I have found Flanking promotions a generally better choice when up against spears. Even with Shock, War Chariots have lower odds of winning, so you might as well increase their survival rate.
A little later in the game, a combination of War Chariots and axes would be good to guard against counterattacking spears, since War Chariots don't get defensive bonuses and would almost certainly lose all the time. In most games, axes (and maybe swords) would gradually replace them as the premier city raiders anyway. As enemy cities accumulate more defensive ratings, those spears become more and more costly to dislodge with War Chariots alone. The loss in mobility that would result from this handing over is usually nothing to worry about, since it corresponds roughly to the time when you need to expand at a slower pace until you can get upkeep costs down.
Speaking of upkeep, be wary of over-expanding with War Chariots. It's easy to fall into this trap since they pack a good punch so early in the game. While judicious use of them might mean smooth sailing for the rest of the game, their careless use can ruin you as you fall hopelessly behind in terms of technology and development paying upkeep, especially on the higher levels. This and the lack of close neighbours are the greatest early adversaries of the Egyptian player.
England: Redcoat (Rifleman)
The terror of your enemies in Civ4 vanilla, this unit is dramatically different in Warlords. In the former, it has 16 strength compared to the normal rifleman's 14 and an additional 25% bonus vs. gunpowder units. Hence, they are uber powerful in their era, quite unmatched by any other unit until infantry. The use of the Redcoat on vanilla is, therefore, quite straightforward. Build lots of them and/or upgrade your CR units to them and go on the offensive. Combine them with cannons for even greater effect and watch the colours on the minimap change rapidly. Even grenadiers are unable to counter them effectively due to their additional bonus. The only way the enemy can really fight back is by throwing lots of cannons at them, but you can always spread your stacks out, and the AI isn't likely to do that anyway. Don't let the enemy get machine guns, though. These are a sure counter to Redcoats on the defense.
In Warlords, however, it's not so easy. Redcoats have the same base strength as normal riflemen. They only retain their bonus vs. gunpowder units. That said, they are still quite effective. Given no terrain or promotion-based bonuses, no unit of the same era can beat them when they attack. They are vulnerable to attacks by enemy grenadiers now, but still not as badly as in the case of normal riflemen. They own any other unit when defending. You can still use this UU the same way, but more careful planning is required. A proper defense against enemy grenadiers must now be provided for, and cannons play a greater role. Do note that Redcoats have no advantage over normal rifles when attacking cities defended by longbows.
In Warlords, you must consider the Churchill factor as well. The new English leader is Charismatic and Protective, making his gunpowder units especially effective. They start with City Garrison I and Drill I and require fewer xp points get promoted. As city defenders, Churchill's Redcoats are certainly a force to be reckoned with. They are also better on the offensive, since Drill helps in any combat situation and, thanks to the free City Garrison, you can better defend newly captured cities against enemy counterattacks. Some players even consider Churchill part of the reason why Redcoats had to be nerfed.
A final point on this UU: Drill IV Redcoats are formidable. They get a total of 5 first strikes and a chance at another (immunity from first strikes are rare enough post-Gunpowder), an extra 10% bonus vs. mounted units and an amazing 60% reduction of any collateral damage sustained. These units are likely to take less damage in every way and win more often. And, in Warlords, Drill counts as a prerequisite promotion towards Cover, Formation and other "vs unit type" promotions. Hence, units with Drill are not condemned by not choosing Combat, should the need for those promotions arise. Especially valuable is the availability of Pinch as a promotion, since it helps to neutralise the threat of attacking grenadiers. The trouble is gunpowder (and melee) units don't get Drill promotions, so it's only possible to create such units by upgrading your archery units to Redcoats, which requires you to set aside a tidy sum. To make matters worse, archery units are generally not used offensively and are thus difficult to promote. However, the good news is Churchill players can do this more easily. With the Protective trait giving free Drill I to your archery units and Charismatic making promotions easier to obtain, you can use crossbows (the most likely candidate, since it has greater offensive value compared to archers and longbows) extensively in the hopes of getting some of them up to Drill IV to be upgraded later.
For BTS players: The Redcoat has indirectly been improved from its Warlords version since all gunpowder units can now receive Drill promotions. That means elite Drill Redcoats are much closer to reality, especially for Churchill. Gone are the days when you have to upgrade archery units to get them.
Ethiopia: Oromo Warrior (Musketman)
BTS only. Musket UUs generally don't get a lot of love, although the ones that the game has to offer are actually quite useful. But even if you're really not a fan of musket UUs, give the Oromo Warrior a try before you knock it. It is immune to First Strikes and starts with 1 First Strike and Drill I and II promotions; that means 2-3 First Strikes and -20% to collateral damage received out of the box. And if you throw the experience from barracks in, you get Drill III Oromo Warriors straight off the assembly line. Just add in Theocracy/Vassalage or a military instructor and you can be training Drill IV Oromos. Naturally, this UU has a potentially high survival rate, even after being battered by siege weapons (thanks to the Drill promotions' protection against collateral damage of up to 60%). They will perform normal muskets' defensive role extra well, and you need not be so hesitant about using them to attack even when faced with knights. Longbows are also less of a worry since Oromos are immune to First Strikes. Moreover, they are draftable, and you can get Drill III draftees with just Theocracy/Vassalage/a military instructor. Knights might give Oromos cause to worry, since they are immune to first strikes and have 1 more combat strength. Fortunately, Drill IV gives a 10% bonus against mounted units, ensuring that your Drill-promoted Oromos aren't necessarily badly threatened by knights.
If those aren't enough, you needn't worry so much about this musket UU getting obsolete quickly (BTS has delayed the advent of grenadiers to prolong the life of muskets anyway) because the promotions will remain on them when they are upgraded to riflemen. You might have read about the elusive elite Drill IV Redcoats. Well, with Ethiopia, Drill IV riflemen are a lot easier to come by. Suddenly those enemy cannons are not so scary anymore, are they?
I hope this guide would help you leverage the different UUs effectively or at least inspire you to be more creative with them. Give all of them a chance! But please note that this guide is written mainly for single player games. Some tips may still be useful for multiplayer, but I can't promise that. This guide also assumes that you are playing as leaders under the normal civs.
Thanks to Robo Kai, kniteowl, Cabert, Wodan, johnny_rico, gusi, UncleJJ, Bjorn190, dime, s.c.dude, drkodos, kristopherb, Elandal, Thyrwyn, Phrederick, Polycrates, Thedrin, agc28, PraetorianSteve, svv, carl corey, Andrei_V, Mr. Civtastic, Thomas G., GeneralGab, Percy, r_rolo1, facistal, jason77024, GoliathFF8 and InvisibleStalke for ideas and contributions that helped make this guide possible.
The different UUs are listed under their civs, in alphabetical order. Note: Due to the additional UUs and changes in BTS, this guide is currently still work-in-progress. So don't be surprised if you don't see an entry for a UU or a relevant BTS note. Feel free to give some advice on the UUs that have not been touched on or on any new tips or tricks for existing UUs. Your suggestions will be appreciated.
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America: Navy SEAL (Marine)
Once you've gotten over the fact that it comes very late in the game, you might realise that the Navy SEAL is actually good UU. A marine replacement, it might seem to be a niche unit. After all, how often do you conduct amphibious attacks (which include those across a river, by the way)? But take a closer look at its unique advantages and you'll realise the potential it has.
Its first strike and first strike chances are not to be taken lightly. First strikes can help you deal more damage to the enemy and comfortably win battles that you might otherwise take heavy damage in or even lose. The free March promotion, meanwhile, allows the Navy SEAL to heal on the go, reducing the time it takes to recover before heading off to another battle. Bringing a Medic III unit along with your SEALs means that as soon as they have attacked, they are eligible for the 30% healing the next turn (5% from enemy territory and 25% from Medic III). So as long as they are at or above 16.8/24 strength, they will be back to full health the next turn. They can also heal right after making an amphibious assault aboard a Medic transport. The SEALs in Civ4 are indeed an elite task force worthy of their name, capable of enduring and sustaining a long campaign.
The 50% attack bonuses against machine guns and artillery are a thick layer of icing on the cake. With SEALs, you don't have to fret when attacking cities defended by machine guns (which are immune to collateral damage) without tanks. Their first strikes also help by negating the machine gun's first strikes. And, also due to their first strikes, SEALs are probably the best stack protectors against enemy artillery attacks. Divide your stack(s) into smaller SEAL-protected groups and you don't have to worry too much about getting overwhelmed by mass artillery.
Whether you have some coastal cities to assault or a land campaign to conduct, Navy SEALs are an excellent unit to bring along with your invasion force. They do come late, but they come at the right time if you're planning on a late domination push that would win you the game.
For BTS players: Gunpowder units can now be given Drill promotions, and the Navy SEAL certainly benefits from this. Besides getting more first strikes and first strike chances, which increase its survivability even more, it also gets up to 60% protection from collateral damage to help against those artillery attacks. Hence, Drill should be the promotion for many, if not most, Navy SEALs.
Arabia: Camel Archer (Knight)
Camel Archers are knights that have a higher withdrawal chance (25%) and don't require horses or iron. You could simply use them like normal knights, but the thing about them is Flanking promotions make them very good at surviving failed attacks (+55% withdrawal chance with Flanking II). This means you don't have to balk so much at attacking a city or a stack that has a defending pike, making them more reliable as an attack unit. Of course, if you end up with no horses or iron, they give you the option of building knights in the first place.
If you're playing on Warlords, stables can give your Camel Archers enough experience points to start off with Flanking I and II, so you don't have to be running Vassalage or Theocracy. Also, you can improve their ability even further by attaching Great Generals to them as warlords. Give a Flanking II Camel Archer the Tactics promotion (+30% withdrawal chance) and it would have 85% chance of retreating from a failed attack. Of course, you might still get unlucky and lose it, especially if you attack at very low odds. It's not 100% withdrawal chance, you know.
Aztecs: Jaguar Warrior (Swordsman)
Traditional whipping boys, these guys get 2 free promotions in Warlords, Woodsman I and Combat I (the latter thanks to Montezuma's Aggressive trait). If you've built those cheap barracks, giving them Woodsman II immediately would allow you to rush a relatively cheap stack of them (Jaguars cost less than normal swordsmen) to enemy cities through forests and jungles, in which they have two moves. Of course, this comes at the price of not being able to give them the City Raider promotion first, but depending on how fortified the target cities are, this may not be such a problem. Jaguars do get the swordsman's inherent 10% bonus when attacking cities.
On a more conventional level, the benefit of the Jaguar is probably similar to that of the Gallic Warrior - better stack protection when standing on a particular terrain. Jaguars can even defend against axemen when positioned in forests and jungles, as they get 70% terrain defense bonus there (+50% from the terrain and +20% from Woodsman I), making them good all-round defenders in this situation. Give them Woodsman II or Shock (both available immediately with barracks) and they would have no need to be afraid of axemen as long as they have trees to cover them. Hence, if the enemy's lands sport plenty of foliage, you may want to bring a few of them along in any case. Note that this applies only to jungles in Civ4 vanilla, where Jaguars get 75% defense bonus (+50% from the terrain and +25% jungle defense bonus).
Jaguars don't require any resource so you can start building them even before hooking up copper or iron. You can also whip them out (probably with unhappy citizens) in newly conquered cities that are not connected to any metal resource, immediately creating some units for either garrison or further offensive purposes and thus helping you proceed with your campaign without having to wait for reinforcements. The value of this UU greatly increases when you find yourself without copper and iron in the first place.
More on the no resource requirement, Jaguars are a sure way to rush a neighbour early in the game. You can plant your second city on the best production site in the direction of your target without waiting for copper or iron to be revealed. Then you build barracks and granary, research IW and start whipping Jaguars out without even having to bother with any resources. Get a stack of them and attack Aztec-style.
For BTS players: With the addition of the Woodsman III promotion, Jaguars have become much more useful in an interesting way. Woodsman III grants 2 first strikes, +50% forest and jungle attack and the ability to heal units on the same tile at the rate of 15% per turn. Since Jaguars get Woodsman I for free and barracks can give them Woodsman II off the bat, they are effectively 2 XP away from becoming the ultimate forest/jungle warriors of their time and effective medics. If you need to take out some enemy units that are fortified in a forest/jungle, especially those that are there to choke your cities, unleash the Woodsman III Jaguars. If you need some quick healing, you have Woodsman III Jaguars. A very handy support unit to have around for early warfare. They are probably still not such effective combat units on their own, but the first strikes might help.
You can even maximise the Jaguar's healing ability by attaching a Great General to it and giving it all three Medic promotions as well. Woodsman III's healing stacks with the Medic promotions (provided they are on the same unit), giving you a whooping 50% healing rate. And this isn't difficult to achieve since Jaguars get free Combat I (required for Medic I) thanks to Aggressive, so you only need 26 XP to get there. Attaching a Great General to a unit gives you 20 XP, so that Jaguar effectively only needs 6 XP, the first 3 of which can be given by barracks.
Carthage: Numidian Cavalry (Horse Archer)
Warlords and BTS only. This is a UU that people are divided about. Some regard it as a good UU (though not great). Others think it is weak. The latter opinion can usually be attributed to the traditional aversion to horse archers, Horseback Riding (HBR) and Archery (techs required to build horse archer-type units). Horse archers have two moves and are good for busting archer-defended cities, but they die to spearmen, rendering them easy to counter. Archery is widely viewed as a useless dead end tech early on, while HBR is fairly expensive, making it tempting to research other more beneficial techs first. The latter's beaker cost also makes it difficult to ensure that your opponents don't have spears yet by the time it's researched. Add the fact that horse archers suffer from a 10% penalty when attacking cities in Warlords, and that the Numidian Cavalry is 1 strength weaker than normal horse archers, it's easy to turn your back on the Carthaginian UU.
However, if you consider it carefully, you may find that it's actually worth something depending on the situation. In Warlords, HBR allows you to build stables (+2 exp to mounted units), which would give your horses an edge in promotions before Vassalage/Theocracy, making the tech more attractive to research early. And the Numidian Cavalry starts with Flanking I, so, with stables, you can give them Flanking II and another promotion (eg. Mobility) right off the bat. This would give them a 50% (20% natural ability + 30% from Flanking I and II) chance to withdraw from losing battles and, if you choose Mobility, the ability to more very quickly even in enemy territory. With the Charismatic trait, it's easy to get your Numidian Cavalry to the next level for yet another promotion. Don't forget that the free Flanking I would not disappear when you upgrade them to knights.
Those are not all. The Numidian Cavalry also gets 50% bonus vs. melee, as well as the 50% bonus vs. siege that horse archers have, making it virtually an improved axeman. It has no need to be overly afraid of spearmen, thanks to the melee bonus. And you can rely on Flanking II to increase the survival rate of your Numidian Cavalry when up against spears, or you can even the odds with Combat I and Shock. If there's no heavy cultural defense, Numidian Cavalry can do a decent job busting cities on their own, although you'll need a good number of them. As active empire defenders or counter units, they are versatile enough, having bonuses against two categories of units. As pillagers, they are excellent since spears, the easiest counter, are not as effective against them - just be sure to build stables and give them Combat I and Shock (of course, you may want a few Sentries). It may seem like a waste of their free Flanking I, but this way the enemy cannot easily drive your pillaging Numidians out. The few Flanking-promoted ones can attack enemy units guarding key resources. Remember to pillage ivory and horses first, since elephants and horse archers are the most effective counters to your UU.
The cons of the Numidian Cavalry are their reduced strength, the 10% penalty against cities and the fact that they can't get City Raider promotions. Once there's significant cultural defense in an enemy city, expect to take huge losses if you don't bring siege weapons along. Even if there's no cultural defense and the city is not on a hill, Numidian Cavalry are actually not as strong as the city's unpromoted fortified archers, so you need to bring at least twice as many. You can beeline to HBR and rush a neighbour with a moderate stack of them to quickly capture a few cities, but don't expect them to carve out a large empire for you.
For BTS players: Horse archers no longer get the 10% city attack penalty, so the Numidian Archer is slightly stronger now. It also gains mounted units' flanking attack ability (not to be confused with Flanking promotion), whereby it does 'collateral damage' to siege units in the stack it is attacking, making it better at countering mass catapults than before. These changes certainly mean that Carthage players have something to cheer about.
Celtia: Gallic Warrior (Swordsman)
Warlords and BTS only. The Gallic Warrior is a much-maligned UU. Most people wonder why an offensive unit is given a promotion for hill defense. How on earth is that going to help him attack cities, which is what it does best?
Attacking a city is the culmination of an offensive movement, which begins with your entering enemy territory. If you're careful, you would want to move your stack along the safest route to the target city as far as possible, which often means favouring forests and hills over flatlands. This is where the Gallic Warrior's free Guerilla I can help. While spearmen protect your stack against mounted units and axemen/crossbows protect it from melee units, a Gallic Warrior on a hill is the best defender against counterattacking catapults and can even take over the role of the other stack-protection units. For example, if your spearman is badly injured, the Gallic Warrior can defend against chariots or horse archers as long as you're on a hill. Thus, while normal swordsmen may be badly injured before reaching the target city in these circumstances, chances are Gallic Warriors would be in better shape.
And note that Gallic Warriors can be promoted with Guerilla II and III. Such units can be a thorn in your enemy's side, running through the hills pillaging mines and maybe raiding a weakly defended city or two, thanks to Guerilla III's movement bonus on hills. The 25% bonus for attacks on hills and 30% withdrawal chance that this promotion gives also make it easier for you to deal with stubborn hill cities. And now that you can build Gallic Warriors with copper in the latest versions of Warlords, this UU can make an extra early appearance for city-busting.
Another neat thing about this UU is the fact that you can upgrade it to more advanced units in its line without losing the free Guerilla I. So, in effect, the benefit of this UU lasts for a long time. Remember that forests can be chopped but hills are permanent.
For BTS players: Somewhat like the Jaguar, this UU benefits from an improvement to its natural promotion branch: the change to Guerrilla III. It still gives +25% hills attack but now it gives a 50% withdrawal chance, making a Guerilla III Gallic Warrior a very effective crack troop. Need to attack that fortified hilltop city before Construction? Guerilla III Gallic Warriors can soften the defenses and have a good chance of surviving even after losing. The 50% withdrawal chance really is quite amazing, outclassing both the Flanking promotions combined. Moreover, since both Celt leaders are Charismatic, it's really easy to get to Guerrilla III. With barracks, your Gallic Warriors can start with Guerilla II and you are only 1XP away from Guerilla III. Sounds like fun.
China: Chukonu (Crossbowman)
The Chukonu has a fearsome reputation. Collateral damage is something well-loved by most Civ4 players, and a respectable non-siege ground unit that has the ability to inflict it would surely become the favourite of some. The biggest weakness of siege units is their inability to defend effectively. The Chukonu, however, can function as an improved crossbowman, thus having an important benefit of siege units without the drawback.
You may find it hard to pinpoint the exact role of this UU, though. Crossbows are primarily a counter unit, designed to help eliminate the threat of enemy melee units, and can in turn be countered by mounted units. If the enemy builds stacks of melee, your Chukonus will tear them apart with their bonus vs melee, first strikes and collateral damage. If the enemy mixes his stacks with mounted units, Chukonus are less effective. Thanks to collateral damage and the extra first strikes, however, they are much less helpless than normal crossbows and are still able to attack such mixed stacks, although you would probably sustain losses initially. The idea is to wear the enemy units down with your extra hits and collateral damage. Given enough Chukonus, there's almost nothing you can't defeat in the field (assuming you are facing units of the same era). But the question arises: Are they more cost effective for this purpose than catapults, since the latter are cheaper? If the enemy only has melee units then the answer is clearly yes. If the enemy has mounted units (which may be immune to first strikes) in his stack, sending in a few scuicide catapults first would probably be a better idea. The Chukonus can do semi-cleanup, dealing even more collateral damage to the enemy units and making them extremely weak and easy for more Chukonus or other units to take out.
You can apply the same concept when attacking a city. Siege units are still needed to remove the city's defenses, but who does the first few assaults would depend on what sort of units are defending the city. If they are macemen and pikemen/spearmen, use your Chukonus. If there are archery/mounted units in the city, use the siege units first, followed by the Chukonus and finally the cleanup crew (if you have any). Remember, Chukonus don't get City Raider promotions, so be prepared to lose some as they attack at lower odds than your CR units might have.
The Chukonu's first strikes are useful on the offense, but they become the primary advantage on the defense. When Chukonus are defending, they won't get to inflict any collateral damage on the enemy units, but their first strikes would be a great boost. First strikes grant chances of hitting the enemy unit before the combat proper even begins, thus improving your odds. The stronger your unit is compared to the enemy's the better first strikes are, since the hits you score would do more damage, thus increasing the possibility of your unit winning without taking much damage. This makes them even better a defense against enemy melee units than normal crossbows. Their first strikes also work well when defending against siege weapons, since they might be able to win before much collateral damage is suffered.
Whether you give your Chukonus Drill promotions for more first strikes is up to you. Note that this UU has higher chances of being promoted than normal crossbowmen, since they are more suitable for an offensive role, making it possible to accumulate quite a few Drill promotions and a lot first strikes. Moreover, if you're playing on Warlords, both Chinese leaders are Protective, so Chukonus start with Drill I, giving you a headstart in that line of promotions. Gunpowder units can't choose Drill, so upgraded Chukonus can be interesting. Incidentally, Protective also makes the Chukonu better at defending cities, thanks to the free City Garrison I promotion.
On a final note, here's a tip on how to get Chukonus early and really overrun your neighbours: Choose Qin Shi Huang as your leader and aim to build the Oracle to grab Metal Casting (requires Pottery and Bronze Working). The Industrious trait makes getting the Oracle viable, even without marble. Metal Casting leads to Machinery, but it also allows you to build your cheap Industrious forges. Build one asap and run an engineer specialist. When a Great Engineer is born, use him to lightbulb Machinery, giving you access to the Chinese UU very early. But do note that Machinery requires Iron Working and Chukonus need the iron resource to be built, so make sure you get this tech researched while waiting for the GE to be born. The worst scenario is finding no iron in your territory. To help prevent this situation, research Iron Working as quickly as possible to locate iron resources and claim them if necessary.
Egypt: War Chariot (Chariot)
At 5 strength, the Egyptian War Chariot is essentially an axeman on wheels with no City Raider promotions but has withdrawal chance. It is a very powerful and mobile unit that can win your game from as early as the Ancient Era.
An Egyptian player who does not have copper has less to worry about. In fact, horses are much more important for him/her, making Animal Husbandry (AH) a priority. And since Egypt starts with Agriculture, which leads to AH, things are pretty much set up for you. Egypt also starts with The Wheel, which is required to build chariots and roads (to hook up those horses). What serendipity! Feel free to delay Bronze Working till you wish to use Slavery, unless it turns out that there are no horses within reasonable distance. If you discover horses nearby, get a settler there as soon as possible and hook it up. You can then begin preparing for your offensive. Chariot rushing has never been so effective.
While the chariot rush tactic of pillaging the enemy's metal mines should still be applied, War Chariots aren't as afraid of spears as normal chariots because of their increased strength. Additionally, you can give them the Shock promotion to help deal with enemy spears that you might encounter. This would also help vanilla players who face enemy axemen, since the chariot bonus vs. axes applies only after Warlords (vanilla players are somewhat compensated by having 20% withdrawal chance instead of just 10%, though). That said, I have found Flanking promotions a generally better choice when up against spears. Even with Shock, War Chariots have lower odds of winning, so you might as well increase their survival rate.
A little later in the game, a combination of War Chariots and axes would be good to guard against counterattacking spears, since War Chariots don't get defensive bonuses and would almost certainly lose all the time. In most games, axes (and maybe swords) would gradually replace them as the premier city raiders anyway. As enemy cities accumulate more defensive ratings, those spears become more and more costly to dislodge with War Chariots alone. The loss in mobility that would result from this handing over is usually nothing to worry about, since it corresponds roughly to the time when you need to expand at a slower pace until you can get upkeep costs down.
Speaking of upkeep, be wary of over-expanding with War Chariots. It's easy to fall into this trap since they pack a good punch so early in the game. While judicious use of them might mean smooth sailing for the rest of the game, their careless use can ruin you as you fall hopelessly behind in terms of technology and development paying upkeep, especially on the higher levels. This and the lack of close neighbours are the greatest early adversaries of the Egyptian player.
England: Redcoat (Rifleman)
The terror of your enemies in Civ4 vanilla, this unit is dramatically different in Warlords. In the former, it has 16 strength compared to the normal rifleman's 14 and an additional 25% bonus vs. gunpowder units. Hence, they are uber powerful in their era, quite unmatched by any other unit until infantry. The use of the Redcoat on vanilla is, therefore, quite straightforward. Build lots of them and/or upgrade your CR units to them and go on the offensive. Combine them with cannons for even greater effect and watch the colours on the minimap change rapidly. Even grenadiers are unable to counter them effectively due to their additional bonus. The only way the enemy can really fight back is by throwing lots of cannons at them, but you can always spread your stacks out, and the AI isn't likely to do that anyway. Don't let the enemy get machine guns, though. These are a sure counter to Redcoats on the defense.
In Warlords, however, it's not so easy. Redcoats have the same base strength as normal riflemen. They only retain their bonus vs. gunpowder units. That said, they are still quite effective. Given no terrain or promotion-based bonuses, no unit of the same era can beat them when they attack. They are vulnerable to attacks by enemy grenadiers now, but still not as badly as in the case of normal riflemen. They own any other unit when defending. You can still use this UU the same way, but more careful planning is required. A proper defense against enemy grenadiers must now be provided for, and cannons play a greater role. Do note that Redcoats have no advantage over normal rifles when attacking cities defended by longbows.
In Warlords, you must consider the Churchill factor as well. The new English leader is Charismatic and Protective, making his gunpowder units especially effective. They start with City Garrison I and Drill I and require fewer xp points get promoted. As city defenders, Churchill's Redcoats are certainly a force to be reckoned with. They are also better on the offensive, since Drill helps in any combat situation and, thanks to the free City Garrison, you can better defend newly captured cities against enemy counterattacks. Some players even consider Churchill part of the reason why Redcoats had to be nerfed.
A final point on this UU: Drill IV Redcoats are formidable. They get a total of 5 first strikes and a chance at another (immunity from first strikes are rare enough post-Gunpowder), an extra 10% bonus vs. mounted units and an amazing 60% reduction of any collateral damage sustained. These units are likely to take less damage in every way and win more often. And, in Warlords, Drill counts as a prerequisite promotion towards Cover, Formation and other "vs unit type" promotions. Hence, units with Drill are not condemned by not choosing Combat, should the need for those promotions arise. Especially valuable is the availability of Pinch as a promotion, since it helps to neutralise the threat of attacking grenadiers. The trouble is gunpowder (and melee) units don't get Drill promotions, so it's only possible to create such units by upgrading your archery units to Redcoats, which requires you to set aside a tidy sum. To make matters worse, archery units are generally not used offensively and are thus difficult to promote. However, the good news is Churchill players can do this more easily. With the Protective trait giving free Drill I to your archery units and Charismatic making promotions easier to obtain, you can use crossbows (the most likely candidate, since it has greater offensive value compared to archers and longbows) extensively in the hopes of getting some of them up to Drill IV to be upgraded later.
For BTS players: The Redcoat has indirectly been improved from its Warlords version since all gunpowder units can now receive Drill promotions. That means elite Drill Redcoats are much closer to reality, especially for Churchill. Gone are the days when you have to upgrade archery units to get them.
Ethiopia: Oromo Warrior (Musketman)
BTS only. Musket UUs generally don't get a lot of love, although the ones that the game has to offer are actually quite useful. But even if you're really not a fan of musket UUs, give the Oromo Warrior a try before you knock it. It is immune to First Strikes and starts with 1 First Strike and Drill I and II promotions; that means 2-3 First Strikes and -20% to collateral damage received out of the box. And if you throw the experience from barracks in, you get Drill III Oromo Warriors straight off the assembly line. Just add in Theocracy/Vassalage or a military instructor and you can be training Drill IV Oromos. Naturally, this UU has a potentially high survival rate, even after being battered by siege weapons (thanks to the Drill promotions' protection against collateral damage of up to 60%). They will perform normal muskets' defensive role extra well, and you need not be so hesitant about using them to attack even when faced with knights. Longbows are also less of a worry since Oromos are immune to First Strikes. Moreover, they are draftable, and you can get Drill III draftees with just Theocracy/Vassalage/a military instructor. Knights might give Oromos cause to worry, since they are immune to first strikes and have 1 more combat strength. Fortunately, Drill IV gives a 10% bonus against mounted units, ensuring that your Drill-promoted Oromos aren't necessarily badly threatened by knights.
If those aren't enough, you needn't worry so much about this musket UU getting obsolete quickly (BTS has delayed the advent of grenadiers to prolong the life of muskets anyway) because the promotions will remain on them when they are upgraded to riflemen. You might have read about the elusive elite Drill IV Redcoats. Well, with Ethiopia, Drill IV riflemen are a lot easier to come by. Suddenly those enemy cannons are not so scary anymore, are they?