Ancient: Of the four eras in Civilization III, Ancient is played with more unique and varied strategies than any of the others. The primary reason is that players at this phase are engaging in unopposed land acquisition, something that is very uncommon in the last half of the game. With this land grab mentality, players need to balance the short-term erosive effects of settlers on their population with the need to build and grow their way out of this era. A wonderful shortcut is the Great Library. Those with conquest on the brain may choose to avoid the advances that lead to this Great Wonder (Alphabet, Writing, and Literature), but do so at enormous risk. The Great Library actually rewards players with civilization advances that at least two of their known competitors already have. On higher difficulty levels, the production bonuses given to computer-controlled civilizations often mean players are constantly trailing in the research game. With the Great Library wonder, you can never fall all that far behind. While on the subject of wonders, it's important to realize the cultural benefits of Ancient Era wonders. These structures can often become the most potent culture point generators simply by the fact that they'll stand the longest. All Ancient Era wonders have the penalty of being obsolete sooner or later, but their cultural contributions will only continue to grow. Depending on your preferred method of victory, you may find yourself building Great Wonders that you have little interest in, only to reap the compounding culture they'll provide. The Ancient Era is the only era that offers two advance enabled government types: Monarchy and the Republic. Depending on your civilization, one may be significantly easier to research than the other. The Japanese and Aztecs (both enjoying Military and Religious Civilization Strengths) start with two of the required four prerequisite advances for Monarchy (Ceremonial Burial and Warrior Code). Selecting either of these civilizations can cut your time to Monarchy in half. Monarchy allows for a large military, the ability to pay for hurried production, and the use of military police. The Republic has its advantages as well, and if research is your game, the increased commerce generated by this government type can accelerate advances. The swordsman is by far the most effective, non-civilization specific combat unit in the Ancient Era. Those with the lust for battle should begin to research Iron Working as soon as possible. Once researched, if you're lucky enough to actually have a local source of iron, you can begin the military campaign of your dreams. This is especially true should you be playing either the Persians (whose Immortals have the highest attack strengths of any Ancient Era unit) or the Romans (whose Legionary defend with the strength of the Middle Ages Pikeman). If you don't have local access to Iron, now would be a great time to start trying to secure it. If you've researched the Writing advance, you can possibly secure Iron through trade. Otherwise, start to amass your primitive spearmen and archers, and then take the Iron from a rival. In short, civilizations wallowing in the Ancient Era can be divided into two categories: those with swordsmen and those without. Another critical advance in the Ancient Era is Construction, which is useful for enabling the building of the Aqueduct and Coliseum city improvements, as well as the Fortress. In Civilization III, it's just as important to defend your territory as it is your cities. If you were depending on a tangle of the silk luxury to keep your grumbling citizens happy, it would be devastating to have your roads between the silk and your capital pillaged. To defend these critical tiles, the mighty Fortress can provide substantial defensive bonuses and bestow the Zone of Control ability to units typically without it. This combination can present a significant deterrent to both the crafty computer opponents as well as the rampaging barbarian hordes that plague the Ancient Era. Middle Ages: The Middle Ages is where the meat of the game begins for me. Strong defensive units, robust naval warfare, and powerful cannons color the battlefields of this era. In addition to this increasingly sophisticated arsenal, you also have access to more Great Wonders in the Middle Ages than in any other era. It's a time in which you can choose to spend a great deal of time exploring each technology or you can machine-gun through, bypassing some or all of the eight optional advances. It's one of my favorites. The advances with which you start this era are all attractive. Feudalism gives you Pikemen and Sun Tzu's Art of War (the maintenance cost-cutting warmonger Wonder). The equally useful Monotheism bestows the Cathedral, a very important element in expanding your territory and the first non-Temple happiness city improvement available. Although Ancient Great Wonders like the Hanging Gardens can also allow you to combat unhappiness throughout the continent, it doesn't accelerate cultural development like the Cathedral, which hurts those cities without the Wonder. Engineering is another potential starting advance in the Middle Ages. While it doesn't give the player any flashy units or Wonders, it does allow road bonuses to persist over rivers and is a cornerstone prerequisite for gunpowder. Basically, you can't go wrong with early Middle Ages advances. The most powerful offensive military units of the Middle Ages are mainly horse-based, so prepare for this before leaving the Ancient Era either through luck, diplomacy, or steel. Knights are the dominating force for much of the Middle Ages since they can defend like a Pikeman, move like a Horseman, and attack like a Longbowman. As long as you have the prerequisite strategic resources of horses and iron, now would be a good time to expand your empire the hard way. Right at the end of this era, Cavalry appear, which are pretty much the be-all end-all of the Middle Ages' offensive military units. Another military highlight of this era is the first primitive gunpowder unit. This is definitely the era where defensive units come into their own. In every case, you'll need some resource (saltpeter for Musketmen and iron for Pikemen), but if your goal is to turtle your civilization, you'll need gunpowder units do it. It's also easy to forget about cannons, which, if gathered in sufficient quantities, can begin to achieve some very useful results. The Ancient Era's catapults were fairly effective smashing town walls, but were next to useless on the battlefield. Cannons are very effective in both shaking a city to the ground and blunting mass attacks against your territory. The Middle Ages offer some great Wonders and city improvements. Newton's University, Copernicus' Observatory, and Universities all can keep the civilization advances coming fast and furious, which is especially crucial on higher difficulty levels without the Great Library. The Military Academy small wonder will finally eliminate the need for battlefield-promoted leaders in order to create Armies. The world's oceans truly become the playground of nations during the Middle Ages, as opposed to the treacherous depths that were feared and avoided in Ancient times. You can now utilize naval trade routes in the exchange of resources after the required advances are researched of course, and the first naval units capable of bombardment are introduced, which is a critical breakthrough and another powerful benefit. For example, Frigates are a naval bombardment unit that now make it much less dangerous to attempt a D-Day, since you can be assured the foreign city you're storming has been blasted for a few turns. The Privateer is a weakened Frigate that can attack another nation's ships without triggering war. Primarily useful as an interceptor against naval landings, which become fairly prevalent during this time, Privateers can keep the other civilizations off balance and irritated. They are a potent new addition to the Civilization arsenal. Industrial: The Industrial Era is ultimately one of conflict, which is why I love it. It's an era of massive nations crashing into each other over strategic resources. Ancient Era wars are easily forgotten, but because of the military hardware available during these times, an Industrial Era war leaves indelible scars on an opponent. In my opinion, Civilization III is most thrilling when balanced, established, and stable civilizations begin to compete directly against one another. At no time is this more evident than in the Industrial Era. In all likelihood, your first goal when entering the Industrial Era is Sanitation. If you stopped to smell the roses at all in the Middle Ages, you've probably got a few cities capped at population 12. By researching the Medicine and Sanitation advances you can build hospitals, which is the city improvement that permits unlimited growth--as long as you have the food. Even if you don't have a large number of population 12 cities, you soon will, so you may as well get these fundamental structures built sooner rather than later. There aren't a lot of Wonders in the Industrial Era, but the ones it does have are very useful. The advances are expensive in this era, so the two free advances given with the construction of The Theory of Evolution are a treat. There is also the Hoover Dam Wonder, which bestows the relatively clean Hydro Plants continent wide. Espionage can enable the construction of the Intelligence Agency, which, not surprisingly, can change the tenor of a game dramatically. When it comes to units, you've got quite an arsenal at your fingertips in the Industrial Era. My favorite units in this era are the Infantry. Unlike units in the Middle Ages, the advance that enables infantry also makes rubber available. There's little you can do to prepare for Infantry because it's typically based on city location. Once Infantry comes onto the scene, bombardment units become even more important. Since two fortified Infantry in a metropolis is a very tough nut to crack, you frequently need to reduce that city's ability to function rather than capture it. Artillery is an extremely useful unit toward that end. It doesn't require a resource, it has decent ranged fire, and when it hits a city, it can destroy an improvement, reduce the population, or damage units. Sometimes, if a city is too difficult to capture, it may benefit you to simply reduce the city to rubble. At the very least, the enemy won't be able to enjoy its full production, and if you pillage the surrounding trade networks, you can prevent them from reinforcing themselves. Don't forget that the naval units of the Industrial Era are some of the game's most effective bombardment units. Battleships and Destroyers are far more mobile than artillery, can't be captured, and have attack values in addition to their bombardment streng!th. Another real highlight of the Industrial units is the introduction of Air Power. Beyond the infrastructure benefits of airlifting between cities and air trade networks, you begin to have access to bombers, fighters, and helicopters. Fighters are capable of minor harassment of ground units and improvements, but truly excel at providing combat air patrol over cities or units. Bombers are like artillery, but have significantly longer ranges and are invulnerable to most ground units. Helicopters can be loaded up like naval transports and then airdrop their units to any tile within their operational range. As the Eras advance, strategic resources become increasingly necessary, but with toys like these to play with, it's more than worth the trouble to secure them. Modern: The Modern Era is the final era in Civilization III and could be the one in which you spend the most time. It's an era dominated by city improvements such as Spaceship Components and is home to the pinnacle of military hardware. By the time you make it to the Modern Era, you'll have a pretty good idea of the type of victory you're aiming for, so it's time to put your opponents out of their misery. In order to accomplish a Space Race victory, you need to focus on securing the advances needed to acquire the ten components for building the spaceship. The first advance is Space Flight, which allows for the Cockpit, Docking Bar, and Engine. Next, the Synthetic Fiber advance enables the Exterior Casing, Stasis Chamber, and Storage components. The Superconductor advance bestows the Fuel Cells and Life Support parts. Finally, the Laser advance allows for the Planetary Party Lounge, and the Satellite advance bestows the Thrusters. In addition, you'll need to enable Rocketry for Aluminum and Fission for Uranium, since they are the two strategic resources that are required to construct the spaceship parts. As you can tell from this recipe, the Spaceship is a massive undertaking. Suppose, however, you've been fairly civil to your neighbors and don't have the industrial base to construct what are essentially ten wonders back to back. Perhaps then you should look to make your civilization the world's inspiration. Beyond being the gateway into nuclear war, the Fission advance also permits the construction of the United Nations. Once constructed, you are guaranteed a pole position in any Diplomatic victory race. If you're behind the eight ball, you can sometimes perform a miracle with the United Nations Wonder. Most competitive civilizations are no doubt experiencing some awful pollution by the Modern Era. Fortunately, there are a number of advances that enable improvements to help combat this production hurdle. It all starts with the Ecology advance, which enables the construction of the Mass Transit and Solar Plant improvements. The Solar Plants are especially useful if you've got coal plants and factories boosting your shield and pollution production. Solar Plants allow similar production boosts without the pollution. Follow this up with the Recycling advance, which allows the construction of Recycling Centers, and you're well on your way to having a large city and low pollution. Combat becomes exceedingly lethal in the Modern Era. Nuclear submarines enabled by Fusion and Tactical Nuclear Missiles enabled by Space Flight create a pretty potent one-two punch. These vessels are invisible except to other submarines and AEGIS Cruisers, so you can safely moor them off the shore of your rival. While they can only carry one missile at a time, a small wolf pack of four submarines can absolutely decimate important enemy cities. ICBMs are even more devastating. Enabled by Satellites, they can deliver a nuclear payload to any location on the globe. Overall: As I mentioned before, my favorite games are those that involve strong, established empires going to war with each other. In these situations, the vocabulary introduced into diplomacy and trade is fantastic, and you can revel in the fun of invading an opponent's continent. This completely shapes my approach to advance research. My overall game strategy is to focus on not falling behind the AI and building large, well-defended, and improved cities in the first two eras. After that, it's World War time. During the Ancient Era, I go to the Tech Tree and queue up the advances leading to Literature. While an optional advance, the Great Library wonder is a critical Wonder for my play style. It pretty much ensures that as long as I'm actively establishing contact with other civilizations, I won't fall too far behind in advance research until at least the late Middle Ages. Plus, it's nice being able to reallocate research gold into entertainment or the treasury. After that, I pursue Monarchy. This is my default government type unless I'm alone on a continent or I decide to go for a heavy culture game--with its corresponding high maintenance costs. Then I simply mop-up any required advances, usually focusing on the Iron Working and Construction branch of the tree. In the Middle Ages, I'm gunning for Gunpowder. It's not a quick trek, particularly because you need to survive the Knights and Cavalry that populate the era, but it's a prudent goal. With the discovery of Gunpowder, I usually am flagging civilizations as targets for future wars. If I've got the saltpeter strategic resource, I will plan on attacking the most vulnerable or unpopular. If I don't, it's time to start heavy diplomacy, swapping maps and making friends from whom I can borrow saltpeter. Next, I may start acquiring naval advances like Astronomy, Navigation, and Magnetism. Otherwise, I'll take advantage of the research already completed and secure cannons with Metallurgy. While they pale in comparison to the Industrial Era's Artillery, they can be upgraded and are fairly effective defensive units. The Industrial Era starts, as it probably will for most players, with Medicine and Sanitation for their hospitals. Without these elements, it's fairly difficult to amass enough population to produce the increasingly expensive improvements and units. Then, it's time to secure the bread and butter of my military: Replaceable Parts. Next, I'll start mass-producing artillery and infantry and then acquire Flight and possibly Amphibious War. Both Amphibious War and Advanced Flight are very useful advances on small island maps, since they enable versatile assault units like the Marine and Helicopter. If I'm attempting a Space Race victory, I'll pick up Espionage since sabotaging production is a very effective way to ensure you launch for Alpha Centauri first. By the time I get to the Modern Age, the stage is usually set for both my opponents and me. If you're not careful, pollution can be a very devastating handicap in this era. While I'm usually good about keeping production cities well staffed with workers to clean them up, I'll sometimes still find Ecology and Recycling worthwhile. I don't always go down this road, but if global warming is turning your grasslands into desert, it can be a lifesaver. After that, I'll usually pick either Synthetic Fibers if I'm feeling the pressure in my campaigns of conquest, or Genetics for it's Great Wonders that sooth and boost the population. Occasionally, Integrated Defense can be an early priority if nuclear weapons are in play. To be honest, though, it's a better preventative measure than cure. Usually, if there are mushroom clouds sprouting across the globe, global warming will starve you and everyone else back into the Stone Age no matter what you do.