In this note I'll try to cover the changes from Civ3/PTW to Conquests which affect strategy in a GOTM game. I won't describe the many other differences except to briefly mention:
1) New and changed Civilizations. When you first encounter a Civ you might want to check them in the Civilopedia. Some previous Civs have changed traits - if that matters to you then check all Civs you meet, not just new ones.
2) New Civilization traits - agricultural and seafaring. Understanding these won't matter much until we play a Civ which has them except for one thing: seafaring Civs get an extra movement point on water and may be able to cross a gap which a non-seafaring AI won't cross.
3) New units. There are a few new units available to everyone. You can check the Civilopedia to learn about these as they become available to build.
4) New bonus resources such as "tropical fruit" (bananas.) You can look up each of these in the Civilopedia when you encounter them.
5) Small stuff. There are lots of minor changes such as tweaking of unit stats and costs, defensive free shots for some units, etc. I consider most of these to be relatively minor and won't detail them.
Changes you've already seen in GOTM
These changes have been made in past GOTMs in anticipation of Conquests. If you've played a recent GOTM you'll already have a feel for these. The changes in this category which I think have significant impact on strategy are the following.
Trading of contacts and trading of maps both become possible in the Middle Ages instead of Ancient Times. Contacts moved from Writing to Printing Press. Maps moved from Map Making to Navigation.
Unit support cost in Republic changed from 1gpt per unit with no free ones to 2gpt per unit with 1/3/4 free ones per town/city/metropolis.
Trading for workers: typically the AIs want about 120g now vs. 30g in unmodified Civ3/PTW.
Lethal bombardment for bombers. This can be used to great (perhaps overpowering) advantage in a Modern Times war!
Corruption, RCP, Forbidden Palace
RCP is gone. Place your cites according to the geography and don't worry about equidistant rings.
The Forbidden Palace does not create a second center for rank corruption. In Conquests the Forbidden Palace only increases OCN (the number of your cities which won't have extreme corruption) and serves as a second center for distance corruption.
In Conquests I recommend building your Forbidden Palace fairly near your Palace (in a city no more than say 1/3 corrupt) to build it quickly. Build it in a city which is in the general direction from your Palace where you expect to expand the most, to gain a bit from its effect on distance corruption. I suggest beginning the build relatively early - on a standard map it would be good to start the FP build when you have about 10 cities, planning to complete it when you have around 20 to 30. The boost to your empire's production will be nice but not huge. So I don't suggest going crazy to build it quickly, e.g. stuffing workers into the city building it. You might want to start it sooner or later than I've suggested depending on your other priorities in the game.
I don't think it is worthwhile to use a leader to rush the Forbidden Palace. Since it no longer makes sense to build the FP in a totally corrupt region you might as well use real production to build it and use leaders for other things.
Moving the Palace and/or FP is now seldom worthwhile. Moving the Palace will often hurt your empire because all cities get their corruption rank from the Palace city - you can't use a Forbidden Palace to maintain productivity in the original Palace region. Palace jumps are probably not worth considering in Conquests.
The maximum corruption for any city is now 90% instead of 95%. This makes large outlying cities a bit more useful than before.
The Courthouse and Police Station now reduce the maximum corruption of a city by 10% each. E.g. a city with a Courthouse will not be more than 80% corrupt regardless of where it is in your empire.
Great Leaders
There are now two kinds of Great Leaders.
Military Great Leaders (MGLs) are the original type. They're produced as before by winning fights with elite units, and with the same odds as before. They've changed in one important regard - they can no longer be used to rush great wonders. They can still be used to rush small wonders, regular improvements, and to create armies. At first this may sound like they've become a lot less useful. But armies have become much more powerful. So much so that MGLs may be more important than ever. I've written a separate section about armies further down.
Scientific Great Leaders (SGLs) are the new type of leader. They are produced by being the first Civ to research a tech. Each time you are the first Civ in the world to learn a tech you have a 3% chance of getting an SGL. (A 5% chance if you are playing as a scientific Civ.) An SGL can be used either to start an "age of science" (increases research for 20 turns) or to rush a great wonder (same as could be done with an MGL before Conquests.)
There's an option to turn off SGLs and I hope the Conquests GOTM will use it. I think SGLs are poorly implemented and we're better off without them. For one thing they're too large a luck factor. For example, 1 out of 33 players will get an SGL on their first discovery of a previously unknown tech. Say Writing in the current game since we start with Alphabet. Those lucky few players can then rush a wonder such as Pyramids! And this is a largely uncontrollable luck factor. We can't "farm" for SGLs as we can for MGLs. With a bit of bad luck it is possible to be the first to learn almost every tech in the game and still not get a single SGL. If SGLs are turned on in the game and you get one, I recommend using it to rush a great wonder. There's a bug in the implementation of the "age of science". And even if that worked properly I think that it would almost always be better to rush a wonder.
A couple of things to watch out for with SGLs:
o You might not realize it when you get one. I've only had one (because in the Conquests games I've played I was usually behind in tech) and I didn't realize I had it for a while. I guess there was a popup message about it, but one which disappeared by itself without needing a click from me. I eventually noticed it in my F3 display.
o You can have more than one unused SGL at a time. However I think that while you have an SGL you will not be able to produce an MGL in battle.
Armies
If you're planning much military action at all you'll want armies - they're very powerful now!
Armies in Conquests:
o Get a bonus to their attack and defense strength. The attack bonus is the total of the attack strengths of all units in the army, divided by 6. The defense bonus is the total of the defense strengths of all units in the army, divided by 6. If you've built the Military Academy small wonder the bonuses increase - the totals are divided by 4 instead of by 6.
o Get an extra movement point. E.g. if the slowest unit in an army has 2 movement points then the army has 3 movement points.
o Have the blitz ability. I.e. they can attack multiple times in one turn, one attack per remaining movement point.
o Can pillage without using a movement point.
o Have the zone of control ability. I.e. they sometimes take a shot at enemy units as the enemy moves past them.
o Have an improved scouting range, seeing an extra tile in each direction.
o Heal slowly even while in enemy territory. They heal quickly in home territory and heal completely in one turn in cities with barracks.
The AI will generally not attack an army unless it is in a city. An exception is a wounded army - below a certain level the AI may attack it. You can generally figure that an army with more than 8 hit points will be able to move around with impunity.
The AI won't build armies.
All of the above sure adds up! Armies are well worth using MGLs to produce. I feel they're over-powered now which is a shame - I wish the AI would attack them and would produce armies of its own to even things out a bit.
One final note about armies: After you build the Military Academy small wonder, you can cash-rush armies! If you are involved in a lot of warfare armies are well worth their rush cost.
Research
The maximum number of turns to research a tech has increased from 40 to 50. So learning a tech the slow way has become a bit less appealing.
The first Civ to learn Philosophy gets a free tech! When you learn Philosophy, after selecting the next tech to research, you'll get that tech immediately if you were first to Philosophy. This makes going for Philosophy a no-brainer I'd say
If you've been playing Civ3, i.e. not PTW, there's a significant change for scientific Civs. Instead of predictably getting the same tech almost every time upon entering a new era, scientific Civs get one of the starting techs for the era at random.
Motorized Transportation can now be reached without researching the bottom path of the Industrial Age tree. This change can be used to get to tanks a bit sooner, which may make them a bit more useful.
There are some other changes to the tech tree (a couple of new optional techs, Radio is gone, spaceship path is a bit different) but none of these greatly affects strategy IMO.
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I think you realise we would all have to give up our jobs for this and though we all are committed there is a limit.
SirPleb!
