OCC guide

The original, and to my knowledge the only, guide to OCC was written by Paul van den Belt. While his work is seminal, it was written at a time when Civ2 discovery was on going and OCC experience was scarce. Nowadays, Civ2 discovery has reached its peak and stabilized. Furthermore, there is a lot more experience playing OCC. Soon after playing OCC I realized some of the shortcomings of the guide, and started thinking about writing a new one.

Well I finally got a chance to do so. I am presenting my writing in this forum first for your comments and critique. Thanks.

Abstract
One City Challenge (OCC) is about winning a game of Civilization II (Civ2) with only one city. There are two ways any game in Civ2 can be won: conquest or being the first to land a space ship. Almost all OCC games are won with a space ship. The strategies and tactics needed for the two approaches are vastly different. This article explains the strategies and tactics needed to win with a space ship.

Author: Ali Ardavan
About the author: I have been a Civ2 player since it came out for Macintosh in late 1980s. I was an avid Civ1 player before that. I discovered CivFanatics website in 1992 and have been an active player and contributor since. The site, specially its GOTM (Game Of The Month) feature, allowed me to vastly improve my game. It was there that I first learned about OCC, and was amazed at the possibility of winning with just one city. Playing OCC became a favorite of mine. I have played dozens of OCC games both within and without GOTMs.

Tributes:
The original, and to my knowledge the only, guide to OCC was written by Paul van den Belt. While his work is seminal, it was written at a time when Civ2 discovery was on going and OCC experience was scarce. Nowadays, Civ2 discovery has reached its peak and stabilized. Furthermore, there is a lot more experience playing OCC. Soon after playing OCC I realized some of the shortcomings of the guide, and started thinking about writing a new one.
I should also pay tribute here to avid OCC players at CivFanatics GOTM whom through their games and forum participation have contributed much to the overall experience and knowledge of OCC: ElephantU, TimTheEnchanter, and OldnSlow.

Audience:
This article assumes the reader already knows how to play Civ2 and is familiar with common tactics like incremental rush buying. Furthermore, it is assumed that the player is adept enough to win at Emperor and Deity levels. The discussions in this article implicitly assume playing at those levels with 7 rivals in the game. While not mandatory, it is extremely helpful and highly recommended, that the readers familiarize themselves with all of the following topics if they do not know it already: power rating, key civ, oedo year, tech hiding, and mechanics of trade. These are adequately covered in the Early Landing Guide by Solo and quoted in the appendix to this article for your perusal.

Rules:
Rules are of course meaningless if you are playing for your amusement only. However, if you want to compare your game against others, as most players do, you should stick to the rules.
1. Anything under Civ2 cheat menu is obviously not allowed.
2. Reloading a saved game to change an unfavorable outcome is not allowed. The one exception to this rule is that you must save before tipping each hut and reload if you get an advanced tribe. You only need to do this if the hut is on plains or grassland, as the game never gives you an advanced tribe otherwise.
3. Acquiring a city whether through building, conquest, or bribery is not allowed. Razing cities is allowed. In my own games I have one exception to this rule which is not present in the original guide: you are allowed to conquer the capital of a rival who has launched a space ship that is going to beat yours. In the same turn and immediately following the conquest you should either remove your forces from the city if they have any movement points left or disband them if they do not. You may not sell any structure in the city. I have added this exception to add a little bit of extra excitement to those close cases and give the human player one final chance of changing the outcome of the game.
4. Building airbases in your city radius is not allowed. Players have reached the consensus that this is an unacceptable exploit (to take advantage of its railroad/farmland effects). The tactic is banned in GOTM games as well.
5. If you are playing on a known map, such as the Earth maps that came with the game, you can look at the map at any point in the game using the map editor.
6. All other known tactics/exploits are allowed.

OCC Strategy in one sentence
The essence of your overall strategy in OCC is to gain a significant tech advantage at the time you are ready to start the space race thus preventing your rivals from building a faster ship that beats yours.

In any Civ2 game the location of your cities matter, in an OCC game it makes a crucial difference. The first step is to do a Map Analysis based on what is visible and if you are playing on a known map (such as earth) based on what you know about the map. Black clicking (viewing unexplored tiles to note their continent number and comparing those numbers to your continent number) can be employed to enhance this further. The goal is to find the closest multi special site on land with ocean access and as many rivers in the city radius as possible. At times you have to choose among multiple possible sites. Here are the points to consider:
1. In a known map the ocean access may not be crucial based on circumstances. For example if you are playing on earth at historical locations and you are anywhere in Europe, Asia, or Africa you know that you will have multiple rivals/trading partners on your land piece. In a game-generated map ocean access is crucial and should take absolute priority over other dimensions of site selection.
2. Final shield output of your city is important during the space ship building phase. The ideal number of shields produced by your city after all terrain improvements (transformation, mining, railroad) and the addition of an offshore platform is 26. It is worth compromising a few food and arrows to try to reach this number. There will be a long discussion later as to why 26 is ideal and what the alternatives are.
3. The more specials the better. Four is the maximum and is often attainable. Make sure you do not neglect specials hidden under grassland. 10 turns of a settler turns the grass into forest and allows you to reap the benefits of the special.
4. Arrow specials (gold, wine, silk, … ) are preferable to food specials (wheat, oasis, fish, …) and shield specials (iron, peat, …).
5. The best initial special is a whale. It gives you a rich mixture of arrows, food, and shields. It does not need any improvements and is not affected all that much by being in despotism (you only lose 1 arrow).
6. Your overall goal is to get maximum arrows, then maximum food, and finally maximum shields. Sometimes a 3 special site with rivers can give you more arrows than a 4 special site without.
7. Other than the specials you want as much plains, grassland, ocean, and forest in your city radius as possible. 1-2 hills are ok even desirable. Jungle, swamp, and desert are also ok in reasonable numbers. Tundra and excessive hills are bad, mountains and glaciers are the worst.
8. Finally, take into account how many turns it takes to go to an ideal location. A closer suboptimal location may be preferable. In a competitive challenging game every turn makes a difference and losing several at the beginning before founding your city may be too high of a price.

Before building your city
If you need to move to build your city, try to pop huts on the way. Huts never give you barbarians before building your first city. The most desirable outcome is a nomad if you have only one settler. Next, or if you already have 2 settlers, is a fast unit such as a horseman. On-path techs are great, gold is good, and off-path techs are bad. Odds of good versus bad are in your favor.

Later in the game
Best outcomes are None units and on path techs. Worst outcome is off path tech. Barbarians do not matter much once you are away from your homeland. You lose a unit, but you usually end up with more units than you need from huts. Nomads later in the game and far away from home are next to useless. Money is always welcome. Overall odds of good versus bad are in your favor, however, I have seen games when too many off path techs have derailed other plans seriously. To err on the side of caution you should refrain from tipping huts till you get Monarchy and Trade.

Ancient era
Your tech goal is Monarchy followed by Trade followed by Mapmaking. Due to tech hiding, the order is not very strict. Often you have to do mapmaking before Trade.

If you only have one settler, your first production goal is a settler. Once you have an extra settler, your production goal is 1-2 units. If you are on a small island build two units, otherwise just one. You will get more units from huts eventually. If you happen to have horseback riding build a horseman, otherwise build only warriors. You should choose to build warriors instead of phalanxes because barbarians can never conquer your city if it is the only city you have, provided you have "some" defense in it. A diplomat or a caravan will defend your city against barbarians in OCC just as effectively. This rule does not apply to an attack by rivals, but the plan is to stay at peace with them.

Your next production goal is a wonder, not just because you need it but also because you typically have nothing else to do. In Deity where you get an extra settler this happens very quickly. Unless you have a starting tech that enables a wonder, you should research Bronze Working as your first tech even though it is not on the path to Monarchy so that you will be able to build something useful.

Your units should head out for exploration and hut popping. As soon as you get extra units from huts send some back home for defense and crowd control. There will not be any barbarian uprisings in the early game so the only risk for leaving your city undefended is from rivals. That early in the game they can usually be appeased if you give them a tech. Overall, the odds are in favor of leaving your city defenseless, but do not do this for a prolonged period of time.

Once you grow to size 2 in Deity or 3 in Emperor you get unhappy citizens. Be prepared for this by either sending a unit home or raising your luxury rate high enough to keep the order. The luxury rate should be at the expense of taxes and not science as scientific progress in early game is crucial.

If you meet any rivals, try appeasing them. In OCC war is most undesirable. Be cautious about tech exchange though. An off path tech can seriously delay you in the early game. Sometimes it is better to refuse an offer of exchange for an off path tech and just give a tech freely to the rival to appease them.

Once you achieve trade, minimize science till you build Marco. Chances are whatever you may want to research next is already discovered by a rival. Marco should be your first wonder unless:
1. You have already met at least 3 rivals and have a good idea where the rest maybe.
2. You have enough shields to build a wonder and Trade has not been discovered yet.
3. You need to beat a rival to Colossus.

Colossus is your other wonder goal for early years. You should refrain from building infrastructure until Marco and Colossus are done because:
1. You do not want to risk losing either of these wonders to a rival. At this point in the game your resources are limited and even though you get a warning one turn ahead (that a rival is about to complete the wonder), most of the times you cannot do anything about it.
2. Marketplaces and libraries are hardly worthwhile in a small city.
3. Temples before Mysticism cost you 1 gold for making one citizen content. You can achieve the same thing through luxuries for 2 arrows. Putting 40 shields towards something that saves you one arrow per turn is not a wise decision.

Marco Polo
Building of this wonder is an important epoch in your game. You should immediately look up your power rating and then assess the situation of all your rivals before contacting any of them. Get a piece of paper and note the following:
1. Techs they have that you do not
2. What tech they are currently researching
3. Whether or not they have mapmaking
4. Who they are at war with

Choose who to contact first based on their attitude towards you, what techs they have to offer, what you have to offer them in exchange, how much money they have, and whether they are at war with someone who has a crucial tech you need.

Once you meet them note their power rating (the number of spoons on the left hand side of the display; zero is pathetic, six is supreme). Exchange techs with them and gift them mapmaking if they do not have it already. If their attitude towards you is not at least Cordial by now, gift them more techs. Offer map exchange next. If the rival does not end the meeting at this point, demand tribute if they are on the same land piece as you and lower on the power rating, otherwise offer alliance and if they are higher on the power rating ask for a gift.

Tech guiding
Right after you build Marco, whether in OCC or a landing game, you should spend some effort guiding the research of your rivals, particularly the friendly ones. Why let them research something you already know? Monitor their current research topic and gift them that one tech when you have it. Then check again the next turn to see if they picked something else you have and repeat the process till they pick something you do not have. You can usually get several techs in mid game this way.

You have to be careful with this. Sometimes the rival will pick an undesirable tech that you do not have and do not want such as Feudalism.

You should stop doing this in late game, for two reasons. One is the obvious one: you want to have a significant tech lead when starting the space race. The other is a pragmatic one: it will typically take too long for your rivals to research anything new in this era compared to you and this becomes just a waste of real time.

Early Medieval era
By now you are a Monarchy who has Marco (or met most of your rivals) and Colossus plus several units keeping order in your city. You have exchanged techs and maps with most if not all your rivals.

Your next production goals are 3 caravans for trade (plus possibly a boat to carry them), Copernicus, Shakespeare, Library, Marketplace, and Aqueduct (not necessarily in that order). Your number one tech goal is philosophy not just because it enables so many other techs but because it gets you a free tech. Your number two tech goal is Republic. You want to switch to Republic as soon as possible. After that your tech goals are what you need to make the aforementioned production goals possible.

Order of production/research depends on your circumstances. Wonders should take priority simply because you can lose out on them. Caravan delivery should wait for Republic when delivery bonuses will be higher.

If you have achieved Mysticism, build a temple when Shakespeare is far away. Cathedral and Coliseum should not be considered. Focus your efforts on Shakespeare instead. If you do build a temple, remember to sell it the turn before Shakespeare is completed.

Once you achieve Republic increase luxuries to allow you to celebrate. Increase the luxuries to the max if you need to keep the celebration going. Growing through celebrations is very powerful. Build a temple if necessary. Delivery of caravans also help in this process. Once you reach a barrier (typically size 8 before aqueduct is ready or size 12 before sewer is ready), lower the rate to the point that you can just keep the order in your city.

Another thing to do when achieving Republic is to disband some of your supported units. You should only need one unit for defense at this point and hopefully you got an unsupported one (None) from a hut already. You probably want to keep units exploring in distant lands. Once their exploration is done, however, you are better off disbanding them than bringing them home. They often use more support along the way than they are worth. Finally, build a diplomat if you have not already. You never know when a good bribery situation may come by.

Late Medieval era
By now you are a Republic who has Marco, Colossus, Copernicus, and Shakespeare wonders plus a library, marketplace, and an aqueduct. You are at peace with most if not all your rivals. You have established 1-3 trade routes.

Your first goal is to have 3 trade routes if you do not already. Next goal is a sewer to allow you to celebrate up to size 21. Following those you want a University and a Bank. Your tech goals are what makes the above possible. Once you have all those, you want Theory of Gravity (for Newton) and techs that get you closer to magnetism (to upgrade your boat to a Galleon that does not cause unhappiness), refrigeration (building farmlands), explosives (if you are behind in terrain improvement or you need to transform terrain which only engineers can do). Democracy is your final tech goal in this era. You need to switch to it to celebrate to sizes above 21, but it is only useful if you have no units away from home and no triremes/caravels.

Throughout the mid part of the game, whenever your treasury falls below 50 contact any rival that you are at war with. In order to gain a cease-fire, they will not ask for gold if you have less than 50, they will ask for some of your technology instead.

If you have a lot of gold, you can buy a warrior from zero for 50 gold and then incrementally rush buy to your production goal. For example, with 125 gold you can build a caravan in one turn.

Normally you would want to deliver the caravans as soon as possible to get the advantage of the continuing trade bonus, but there are circumstances where it may be wiser to delay the delivery of the caravan by one or two turns. For example, if you have almost discovered your next science advance the one-time science bonus of the caravan will be mostly wasted so you could park your caravan next to the destination city (assuming it is safe to do so) until you discover that advance and apply the full science bonus to the next advance.

Industrial era
By now you are a Democracy who has Marco, Colossus, Copernicus, Shakespeare, and Newton wonders plus a library, marketplace, aqueduct, bank, university, and a sewer. You are at peace with most if not all your rivals. You have established 3 trade routes.

If you have already achieved refrigeration, build a supermarket. Your settler/engineer should be busy creating farmland on all irrigated tiles. If there is a lot of work to be done, you may want to bring in extra help by building an engineer or bribing one away from your rivals. If you bribe one closer to their homeland than yours, it will be unsupported and does not cost you a citizen. However, such bribery tends to be very expensive. When you are completely done with all transformation, irrigation, farmland creation it is time for the final round of celebrations to max size. Depending on the amount of land on hand this may be pretty late in the game. I have had cases when this happened when I was building space ship parts. Regardless, once you reach the maximum size, there is no need to keep your aqueduct or your sewer system, so go ahead and sell those off.

Your number one tech goal in this era is automobile to allow the building of superhighways. Factories can wait and in fact should wait if you are behind in terrain improvement and your settlers/engineers are backed up already (cleaning pollution would make matters worse). Build a stock exchange and then food caravans. If you have enough food caravans on hand for your eventual victory, and expect hostilities near the end build some defensive infra structure such as city walls, barracks, seaport, and coastal fortress.

Around this time you should start paying even more attention to micromanaging your science output. In Civ2 the science output of one city can only contribute to the research for one scientific advance; any excess beakers from the city making the discovery are wasted. Since you have only one city in an OCC game, this means that you should carefully adjust the science rate and the number of scientists in your city to minimize that waste. The way I do this is as follows: first I will set all surplus citizens to scientists and then I will maximize the science rate. You will now see that you will make your next discovery in for example two turns. Now you will lower your science rate to the lowest percentage that will still allow you to make a discovery in that many turns. After that you may be able to change scientists to tax collectors until you have just enough scientists to keep your discovery rate at two turns. When you make your next discovery you will usually have to change one more tax collector to a scientist to keep your discovery rate or you may have to raise your science rate by 10%. In the latter case you can of course change some scientists back to tax collectors.

You can find the total number of beakers needed for the next advance by having no scientists and setting your science rate to zero. The number of turns for the next discovery that is now displayed is the same as the number of beakers you need. Upon a delivery subtract from this the one-time science bonus from the caravan (which is the same as the gold bonus) and you will have the number of beakers you still need to discover the next advance.

Around this time you should be a little careful about what techs you give away to your rivals. For example, avoid sharing combustion which is a prerequisite for flight. You do not want flight discovered before you are ready to discover it yourself, because a premature flight discovery will obsolete the Colossus and slow your science progress.

Once your rivals achieve Industrialization, almost certainly at least one of them will go after Communism. This will obsolete Marco and stops you from monitoring your rivals closely. If you need to keep on monitoring them, consider researching Espionage and building a spy (or two) for establishing embassies. This is also a reason to refrain from gifting Industrialization.

Modern Era
Build modern infrastructure (mass transit, offshore platform, manufacturing plant, …) while going after Computers. Meanwhile avoid Flight. Plan ahead to finish building a research lab the turn after you get Computers. This will give you an immediate 33% boost in science which is very much needed.

Nuclear power is your other goal in this era. It allows you to build a nuclear power plant which reduces the chances of pollution while increasing the shield output of your city by half of your base shield output. It also adds one to the movement points of your boats.

Of all the choices you have for a power plant, Nuclear is by far the best. Regular power plant costs as much in shields (160) but increases rather than decrease pollution. Hydro plant costs 240 shields instead of 160 and is as clean as Nuclear. Solar plant costs 320 shields and reduces pollution the most, but it comes so late in the game (in terms of enabling technology) that for OCC it is just out of the question.

Flight
You want to delay Flight as much as possible because it makes Colossus obsolete. Once you achieve Flight, you should zoom to Space flight. After that the goals are the remaining techs needed for a space ship: Plastics, Superconductor, and Fusion Power.

After fusion power, go after Stealth. You may not need it, but if you do you cannot afford to wait to get it. After stealth you really do not need to discover anything else. If funds are short set your research rate to 0%, your tax rate to 100%, and convert all the extra citizens into tax collectors. You may also sell off your research lab, your university, and your library if needed to help build your space ship parts.

Meanwhile avoid contact with your rivals. They are likely to cancel alliances at this point in the game or start wars if you do not share what they want with them. You should avoid giving them Flight and Advanced Flight because it will significantly increase the reach of their attack units. You should also avoid giving them space race techs since they can build a space ship faster than you can. The designers of the game programmed a fairly decent AI when it comes to the space race, it is certainly superior in intelligence compared to other aspects of the game.

If you have to share, share space flight first, then superconductors, and finally fusion power. Do not share Plastics unless you are assured a win in the race. When the rivals get space flight they tend to build more structurals than they need. This works to your advantage by both keeping them occupied longer and slowing down their eventual space ship. The AI is programmed to never build more than one set of modules. It will however try to build a faster ship than yours.

It is best to be ready defensively before you build Apollo and start the space race. If there are rivals on your land piece conflict is all but certain. At a minimum build city walls, SAM, and barracks. If you are surrounded by multiple rivals also add an airport, seaport, and coastal fortress. Disband all your ancient supported units and replace them with modern vet units. Keep your None units. Build fortresses in your city perimeter and put at least one unit in each even if it is a van. If you have an idle settler/engineer build rail road to your fortresses. If your rivals have Flight or Advanced Flight one of your defensive units should be a fighter plane (stealth fighter if you have the tech).

Space ship parts come in three varieties: structurals costing 80 shields, components costing 160, and modules costing 320. The ideal space ship for OCC has 15 structurals, 3x2 components, and 1x3 modules. Your goal is to build a part per turn. This is a very important goal since at this point in the game the rivals have in all likelihood ganged up against you and are out for blood.

A minimum launchable ship may have as few as 15 structurals, 2 components, and 3 modules. However, that ship takes 36 turns to arrive. With only two extra turns you can produce another set of components that will cut that down to 21 turns reducing the total number of turns from the start. With another two extra turns you can produce another set of components that will cut that down to 15 turns again reducing the total number of turns from the start. If you spend yet two more turns building another set of components, however, the 15 structurals is no longer enough and you have to have at least 17 structurals. This means 4 extra turns and what you get in return is reduction from 15 year travel time to 13, thus increasing the total number of turns from the start. Since you want to finish in as few turns as possible, before your rivals get an upper hand on you or build a faster ship, the ideal ship is 15s3x2c1x3m.

At first glance the ideal situation would seem to be a city that produces 80 shields after support. This is what Paul recommends in the original guide as well. However, in my opinion that is not so. With factory, power plant, and manufacturing plant each giving you a 50% additive boost, you need 32 base shields to get to 80. Since you need several units that cost you support, your city should produce at least 34 base shields (for a total of 85 shields allowing 5 supported units). This amount of shields is impossible to achieve if you have a lot of ocean in your city radius and very hard to achieve in other cases. Paul realized this and recommended mining your grasslands to forest, but that takes time and cannot be done very quickly. If you spread the work over many turns then you lose the arrows and the food for an extended period of time which has a significant negative effect.

The better plan is to go for a city that produces 60 shields after support. With 26 base shields you can get 65 shields allowing support for 5 units. Getting to 26 is far easier and would typically not require mining grassland to forest.

At times you are in situations where even 26 base shields is not possible. For example if you are stuck on a tiny island with no whales in your city radius. In those cases, you should opt for 50 shields after support. In extremely rare circumstances you may have to settler for 40 shields after support. One example would be a one tile island with no access to whales and the need to support more than 2 units. In such a case you would get only 21 base shields which yields a total of 52 shields and with more than 2 supported units your final production falls into the forties.

How to produce one space ship part per turn:
Structurals
At 80 you need not do anything special.
At 60, buy a temple from zero for 160g and switch to SS Structure. This will cost 15x160= 2400g.
At 50, buy a temple from zero for 160g. Switch to a granary and buy it for 40g. Finally switch to SS Structure. This will cost 15x(160+40)= 3000g.
At 40, buy a temple from zero for 160g. Switch to an 80 shield structure you do not have such as an aqueduct and buy it for 80g. Finally switch to SS Structure. This will cost 15x(160+80)= 3600g.

Components
At 80, buy a temple from zero for 160g and switch to SS Structure. Buy the strucrture for 240g. Switch to SS Component. This will cost 6x(160+240)= 2400g.
If you can spare a food van, start a wonder, feed the van, then switch to SS Structure and proceed as before. This will save you 280g per van.
At 60, buy a temple from zero for 160g and switch to SDI defense. Buy SDI for 320g and switch to SS Component. This will cost 6x(160+320)= 2880g.
If you can spare two food vans, start a wonder, feed the vans, then switch to SS Component. This will save you 240g per van.
At 50, the van-less method only works if you can build a hydro plant (need to check on the availability). Buy a temple from zero for 160g. Switch to a hyrdro plant and buy it for 400g. Finally switch to SS Component. This will cost 6x(160+400)= 3360g.
If you can spare two food vans, start a wonder, feed the van, then switch to SS Structure and buy it for 120g. Switch back to wonder and feed the second van. Switch to SS Component. This will save you 220g per van.
If you can spare only one food van, buy a temple from zero for 160g. Switch to SS Structure and buy it for 240. Switch to SS Component. This will save you 160g per van.
At 40, proceed exactly as you would for 50.

Modules
The van-less methods in this case are the same regardless of the number of your shield output.
If there is a 300 shield wonder available, buy a temple from zero for 160g. Switch to the wonder and buy it for 1120g. Switch to SS Module. This will cost 3x(160+1120)=3840g.
If there is not a 300 shield wonder available, buy a temple from zero for 160g. Switch to SS Module and buy it for 1200g. This will cost 3x(160+1200)=4080g.

At 80, start a wonder, feed 5 vans, and switch to SS Module. If there is a 200 shield wonder that is available you may rush buy after 0-3 vans to that wonder then add the last van.
At 60, buy a temple from zero for 160g and switch to SS Component. Buy it for 560g. Switch to a wonder and feed 2 vans. Switch to SS Module. This will cost 3x(160+560)= 2160g.
At 50 and 40 start a wonder, feed a van, and switch to SS Structural. Buy it for 120g. Then switch back to a wonder and feed 4 more vans. Finally switch to SS Module. This will cost 3x120=360.

Just to compare, if you have 15 food vans and pay for everything else the total costs are:
At 80 shields: 0+2400+0(plus 15 vans) = 2400
At 60 shields: 2400+(3x480+3x0(plus 6 vans))+3x440(plus 9 vans)= 5160
At 50 shields; 3000+3360(assuming hydro plant)+360(plus 15 vans) = 6720
At 40 shields; 3600+3360(assuming hydro plant)+360(plus 15 vans) = 7320

Note that there is not all that much difference between 40 and 50. 80 costs least but in my opinion the amount of settler/engineer effort it takes and the loss in arrows and food is not worth it. Late in the game a delivery can easily bring you about 1000.

Furthermore, in a city producing over 85 shields even with recycling center and mass transit you will likely be getting pollution most turns. This means that you need to keep 2 engineers till the end for cleaning pollution. Indeed Paul recommends in the original guide to use a couple of engineers exclusively dedicated to cleaning up the pollution and not building a recycling center or a mass transit. This of course means two fewer citizen scientists and two extra shields in support. The extra support reduces the number of units available for defense. To compensate for this we need to increase output to 87 which translates into 35 base shields which could mean yet one more grassland that has to be turned into forest. With 65 shields, recycling center and mass transit are sufficient to eliminate pollution or reduce it to a rare occurrence.

My own preference is to get my city to 65+ shields and have at least 6 food vans on hand. Paul of course advocated 85+ shields. An avid GOTM OCC player, ElephantU advocated output in the 40s and 50s, stockpiling vans, and skipping the manufacturing plant and the two otherwise off-path techs (Mobile Warfare and Robotics) that it requires. Part of his argument for lower output was not having to deal with the inevitable pollution.

Of course you can drastically cut your cost down by disbanding a unit rather than starting your build from zero. If you have a lot of ancient units from huts this tactic can save a lot of gold. However, keep in mind that if you get attacked those units are quite helpful as cannon fodder absorbing enemy hits while you respond. Furthermore, you can park them in the perimeter of your city to block the pass of approaching diplomats. This is a common tactic of the AI to send two diplomats towards you while still in peace. The two of them move together and since they are a pair you cannot dismiss them. Being in democracy you cannot attack them either. Unless you can block their approach they will steal a tech and in this phase of the game that could be the difference between wining and losing.

Hanging Gardens
3 happy citizens mean far easier celebrations. If you are still in monarchy, you get an extra arrow wherever one is present. In republic, you get an extra citizen. While this is quite useful, getting 3 early wonders (Colossus, Marco, and Gardens) is very difficult with only one city and even if you succeed it often means you risk losing out on Copernicus or Shakespeare. I have often built Hanging Gardens when I had Pottery, had already accumulated 200 shields, and because of off path techs cannot switch to either Colossus or Marco.

Lighthouse
When stuck on an island with no trading partner and no land within a trireme’s reach, Lighthouse is the classic way out. However, just like the case for Hanging Gardens, it is extremely difficult to get 3 early wonders with just one city. I recommend zooming for navigation instead.

King Richards
Ordinarily by the time you can build this wonder, OCC or otherwise, there is enough money on hand for rush buying that King Richards is not among the best wonders to pick. However, when you are stuck on a small island with very few available shields King Richards becomes a necessity, especially in Republic. I once played an OCC on earth starting in Hawaii. There was only one fish within my city radius. In monarchy I had a single shield to work with. Needing a boat I had to build King Richards before switching to Republic otherwise I would have been faced with a situation when my city produced zero shields.

Magellan
In OCC you typically have one boat. Even if you have two, spending 400 shields to increase their movement by two is unwise.

Eiffel
After launch this is a good one to grab to ease tensions if you are not busy producing military for defense.

Leo
In OCC you typically have only a few units. Furthermore, because you are typically at peace prior to the space ship phase you do not really need updates except for your boat and your settler. By the time you do need updates for your military units Leo is obsolete anyways. Spending 400 shields to update your boat and some unsupported units, while useful is not worthwhile.

Darwin
By the time Darwin becomes available your city is probably producing a new tech every 2-3 turns. If your treasury is medium it will take you about 16 turns to produce 8 vans for this wonder (one turn to seed, one turn to rush buy). If you are richer, you can do this in 8 turns. In either case, two techs are not worth it. However there are circumstances when it is worthwhile to build Darwin:
1. Due to largess of your allies and the frequency/quality of your deliveries you have more cash than you need. Use a van or two and rush the rest of Darwin.
2. You are hurting big time due to lack of a crucial tech. This happened to me in the aforementioned Hawaiian OCC. When King Richards was made obsolete by Industrialization, I had a city which produced one shield and that was being used to support my only unit: a boat. Getting to miniaturization was crucial and speeding it up with Darwin more than worthwhile.

Another tactic advocated by some players regarding Darwin, and not just in OCC games, is to share Railroad with rivals who are friendly. Then when you get the message that a rival is about to finish it, give that rival all your techs. They will discover two techs you do not have and within a few turns you can exchange for those. One way this plan goes awry is when the rival chooses Communism as one of those techs and you do not have embassy with that rival. Not knowing what else they have you may accidentally research the same thing yourself. (Check this)

UN
Building UN helps with the often unavoidable conflict near the end. It will also reopen the embassies that you lost when Marco went obsolete. None of this is crucial at this stage of the game and typically not worth 12 vans. However, if you have more cash on hand than you can use, this is not a bad way of spending it.

SETI
Why spend 600 shields when you can get the same effect from a structure that costs only 160? Typically there is no good reason and that is why SETI is rarely built in OCC games. However, there is one case that it becomes worthwhile: One of your rivals is quite advanced in science and likely to be not far behind you in the space technologies. Letting them grab SETI could mean losing the space race. Even at one space ship part per turn, you cannot compete with a rival who has multiple cities and all the needed techs. Typically you overcome this handicap by being far ahead in science. When that is not the case, denying them SETI is worthwhile particularly when you have enough cash on hand to partially rush it.

ElephantU, an avid GOTM OCC player and an expert on this tactic explains it this way : “When you notice a blocked supply that does not have a caravan or freight "en route" nor a corresponding trade route locked in you can "cash in" a food van to free it up. It should free itself up in 16 turns or less anyway (the "Solo cycle"), but if you have a chain or a nearby demanding city it can be made and delivered several times in 16 turns. Switch the city to a Wonder, deliver any food van, and check the supply list: the blocked one should be freed, so just switch back to van production and finish it that turn. The advantage of delivering to yourself, aside from proximity, is that you get 25 shields toward the new commodity van, and if you are doing 25 per turn already it will cost you nothing but a lost food van. Beware trying this around the time of getting Pottery, Ind, NucFis, or your 32nd non-starting tech: the priority list could change radically on you at those times.”

In my experience, the most challenging OCC games are at emperor level on earth with a starting position in the Middle East, Europe, or North Africa. You will have rivals on several sides and you will be attacked during the end game. In my opinion, in OCC, an emperor level game is more challenging than deity. That extra settler at the beginning more than makes up for the one extra unhappy citizen and a more capable smarter AI.

Great gob and nice guide!

Some notes:
It would be very useful for new players I you add links to "resourse pattern", "oedo years" etc.

It's interesting to see what sizes of the city should be fine at the beginning of periouds-eras.

Also - what should usually be prioritized after Monarchy - food (growth), commerce (scince) or shileds (wonders)? Or that depends on situation?...

And - it's interesting to play without popping huts at all. Therefore, less random, and no reloads at all).

Nice piece of work!
I have just been flipping through, but will give it a closer look sometime.

Ali Ardavan said:

Furthermore, in a city producing over 85 shields even with recycling center and mass transit you will likely be getting pollution most turns. This means that you need to keep 2 engineers till the end for cleaning pollution. Indeed Paul recommends in the original guide to use a couple of engineers exclusively dedicated to cleaning up the pollution and not building a recycling center or a mass transit. This of course means two fewer citizen scientists and two extra shields in support. The extra support reduces the number of units available for defense. To compensate for this we need to increase output to 87 which translates into 35 base shields which could mean yet one more grassland that has to be turned into forest. With 65 shields, recycling center and mass transit are sufficient to eliminate pollution or reduce it to a rare occurrence.

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So far, I have been follow Paul's recomendation, kept 2 engineers by as "clean-up crew" during the end and didn't care for any kind of pollution prevention. And that made me think about

Ali Ardavan said:

Leo
In OCC you typically have only a few units. Furthermore, because you are typically at peace prior to the space ship phase you do not really need updates except for your boat and your settler. By the time you do need updates for your military units Leo is obsolete anyways. Spending 400 shields to update your boat and some unsupported units, while useful is not worthwhile.

Click to expand...

So, assuming you will need two engineers in the end, why not upgrade your settlers? If you start with two settlers, you still have one left that has not settled, and you might have one from hut popping. Or you could bribe one nearby AI, although expensive, it won't require support afterwards.

So I thought it might occasionally be useful to build Leo's, although it does little, but that little might be quite valuable. Side-effects would be that your trireme turns to transport (although I love to have a nuclear powered trireme in the end ), and some commoditied vans turn to freight which will increase the payout.
Never did a detailed calculation about this though, but I am no mathemagician.

RedKi-rr said:

It would be very useful for new players I you add links to "resourse pattern", "oedo years" etc.

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I agree. My plan is to add all that stuff to the appendix as text rather than links. Links get broken over time. I left the appendix out here, since this is just a draft for comments by fellow CFCers.

RedKi-rr said:

It's interesting to see what sizes of the city should be fine at the beginning of periouds-eras.

Click to expand...

That depends on your geography and whether you start with 1 or 2 settlers.

RedKi-rr said:

Also - what should usually be prioritized after Monarchy - food (growth), commerce (scince) or shileds (wonders)? Or that depends on situation?...

Click to expand...

I believe I have mentioned that, OCC or not, prior to discovering Trade emphasis should be on science. Then science should be minimized till Marco is built. After Marco, it depends on the situation.

Major Advantage said:

So I thought it might occasionally be useful to build Leo's, although it does little, but that little might be quite valuable.

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I agree as long as the emphasis is on the word occasionally. As you noticed there are many wonders that are not even mentioned. Those are the wonders that are not useful in OCC under any circumstances that I can think of. The fact that Leo is mentioned means that there are circumstances when it might be useful, however, most of the time the benefits are not worth the cost (8 vans which at that point in the game means 16 turns of production aided by partial rush buying).

Democracy is your final tech goal in this era. You need to switch to it to celebrate to sizes above 21, but it is only useful if you have no units away from home and no triremes/caravels.

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If you are supporting a single unit, you can always build a temple to overcome that unhappiness. The temple will make the 2 citizens content, which are then made unhappy by the unit penalty; this prevents that penalty from hitting the citizens made happy by luxuries. I'd say that spending fifty or so gold (after paying maintenance and remembering to sell the Temple when you've finished) is preferable to waiting until you can get rid of a boat.

By the time Darwin becomes available your city is probably producing a new tech every 2-3 turns. If your treasury is medium it will take you about 16 turns to produce 8 vans for this wonder (one turn to seed, one turn to rush buy). If you are richer, you can do this in 8 turns.

Click to expand...

An unsuspecting reader might get the idea that it is cheaper to rush caravans from scratch than it is to rush a wonder directly. This is not the case once you can no longer build warriors. You might want to consider re-wording this.

Building UN helps with the often unavoidable conflict near the end.

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Are you sure about this? In my experience, once you launch a spaceship, enemy civs don't talk to you at all, so UN is worthless. Unless you mean in the time leading up to the launch? If so, a more expensive alternative is Manhattan Project and a Nuke (but it doesn't require communism, which is, IIRC, off path), and the other civs will treat you much nicer for a while (I remember doing this once in an OCC, and I think it stopped the Russians from attacking me). Of course, if someone gets Rocketry, it will be more difficult to get SS components if you were planning on using SDI to get the right shield multiple.

I have been a Civ2 player since it came out for Macintosh in late 1980s. I was an avid Civ1 player before that. I discovered CivFanatics website in 1992 and have been an active player and contributor since.

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Are you sure about these dates? They seem to be about 10 years off. IIRC, civ 2 wasn't released until 1996.

Prof. Garfield said:

If you are supporting a single unit, you can always build a temple to overcome that unhappiness. The temple will make the 2 citizens content, which are then made unhappy by the unit penalty; this prevents that penalty from hitting the citizens made happy by luxuries. I'd say that spending fifty or so gold (after paying maintenance and remembering to sell the Temple when you've finished) is preferable to waiting until you can get rid of a boat.

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Interesting point. I never realized that. It is indeed a good alternative.

Prof. Garfield said:

An unsuspecting reader might get the idea that it is cheaper to rush caravans from scratch than it is to rush a wonder directly. This is not the case once you can no longer build warriors. You might want to consider re-wording this.

Click to expand...

Excellent point again. This only works when you can buy warriors from scratch for 50g.

Prof. Garfield said:

Are you sure about this? In my experience, once you launch a spaceship, enemy civs don't talk to you at all, so UN is worthless. Unless you mean in the time leading up to the launch? If so, a more expensive alternative is Manhattan Project and a Nuke (but it doesn't require communism, which is, IIRC, off path), and the other civs will treat you much nicer for a while (I remember doing this once in an OCC, and I think it stopped the Russians from attacking me). Of course, if someone gets Rocketry, it will be more difficult to get SS components if you were planning on using SDI to get the right shield multiple.

Click to expand...

Good point again. I must make sure these are added.

Prof. Garfield said:

Are you sure about these dates? They seem to be about 10 years off. IIRC, civ 2 wasn't released until 1996.

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My bad. That was a typo. I meant 1990s not 1980s.

Though I rarely play OCC, and don't claim to understand it well, this work seems a great addition to Civ2 lore ! Ali is the strongest active OCC practioner, so this guide can be trusted by all. I hope it will find a place in the War Academy here, and in the GL at Poly.

Ali - ElephantU was also mighty OCC talent, and he also had plans to write a updated OCC guide. He started an OCC comparison game a few years ago (about the time he quit playing gotms, with me and solo and 1 or 2 others), to support that idea. He and solo had some fascinating discussions, which I could hardly follow, but which seemed to me far beyond the ideas in the Paulicy. IIRC one of them (or both?) favored early republic over monarchy, for example. Sorry I can't be more specific, but if you can find that thread, it might be of interest.

Thank you Peaster for the praise. It will be an honor for the final work to be worthy of the GL and War Academy.

If anyone knows how to get in touch with ElephantU, I would love to see those discussions. I will send him a private message right away.

Comparison games are great, and that is why I love GOTMs so much. We have only played one OCC in GOTMs and for some reason it got very few participants (only two). I hope we have another one soon and more people choose to participate.

Thanks for raising the issue on Early Republic. I should have at least a paragraph on that in the guide. My own feeling is that Early Republic is not such a great idea when you expect a lot of huts; otherwise it is worthwhile. Huts contribute in two ways against Early Republic: supported units and techs not immediately on your path. Both of course work against Monarchy as well. However, in Monarchy up to 3 units cost no upkeep and as soon as you reach that limit you can send one unit home for disbanding should you get a fourth. Furthermore, with Republic requiring one more prerequisite tech than Monarchy off path techs can hurt more.

This also reminds me of one more issue that is worth a paragraph: When stuck on a tiny island with no larger land nearby, one should consider having Trade as the first goal. In such cases there is nothing to explore even if you build a Trireme and thus Marco becomes more vital than it already is. If an analysis of the situation reveals that shooting straight for Trade allows Marco to be finished earlier then Trade should take priority over Monarch/Republic. If I recall correctly, I once played such a comparison game myself and the result showed clearly that putting Trade first made a significant difference.

This is what the system told me when I tried to send a private message to ElephantU:
"ElephantU has chosen not to receive private messages or may not be allowed to receive private messages. Therefore you may not send your message to him/her."

I found the OCC comparison game at

http://test.apolyton.net/showthread.php/131262-OCC-2005-Game-1/page2

I don't think you need a password to view it. IMO the discussions between elephantu and solo are worth a look, though you may be beyond that. IIRC solo "won" via early republic, but I'll let you draw your own conclusions, if any. Not sure if the starting save is still there, but I might still have it, if you are interested in trying it.

Thanks for digging it up. Unfortunately, it does require a password; worse yet, it gives you a modal form that prevents you from doing anything else till you give it a username and a password. I had to quit my browser to get rid of it.