CUSTOM TECH TREE DESIGN for Civ2 - by Kobayashi
Date Posted: November 20, 2001
It is quite common to see a scenario without any research these days, which is quite a shame as the tech-tree to me is one of the more important dimensions of the Civ2 game engine. Sometimes a half-hearted effort is made to have a few items available for research at 10% of the normal rate but this too seems to give the feeling of incompleteness. One reason this is hapenning is that redoing the tech tree is probably the most user-unfriendly aspect of scenario making. I have been asked how I have managed to make completely new trees for my multi-player scenarios and the answer has always been - proper planning and the right sequence.
Why waste timing bothering
1. Research adds to the identity
of your scenario. It helps to reinforce the atmosphere that you are
trying to portray.
2. Research increases the depth of your scenario. There is one more dial to fiddle with. Do you emphasize research or taxes? Will you sacrifice population growth to have more scientists?
3. Research increases the strategy element. You can choose between more units now or better units later.
4. Research increases variability. No only can you vary your own strategy, the actions of the AI may differ each time you play depending on what they research. Using tech discovery as a trigger for events instead of setting them to turn X does wonders for replayability.
5. Research reduces monotony. With new units introduced gradually and old units becoming obsolete, the game will continually evolve. Also, the player will not be flooded with a few dozen unfamiliar choices of what to build at the onset.
6. The Civ2 engine is just not well suited to a straight forward slug-a-thon type game.
7. To show you can do it. It is
the hallmark of a great scenario and shows overall mastery of the
Civ2 scenario creation process.
Some might argue that in many cases it is not appropriate to have research. That might well be true in a few cases, for example the Oddesy scenario, but for the majority I would argue against this. Afterall, I managed to do a full tree in my World War II scenario even though it lasts for only five years (when in difficulty, you can always name your advances after new units or improvements).
Wouldn't you like something like this for your scenario?
First Things First
The first thing to do is to decide the units which you will be using. The graphics are not required at this stage, just the names and perhaps the owners of those units which cannot be built by all tribes. There are other issue involved like the sound slots, you should refer to my earlier articles like "Getting the units right from the beginning".
The next thing to do is to determine the city improvements that will be appearing. At this stage you don't need to name them yet but you can drop those which will not be needed. For instance, mass transit won't be needed if your scenario has pollution turned off. Finally, do the same for the wonders, dropping those which are inappropriate (like lighthouse in an all land scenario). When this is done, list down the order you want the units, improvements and wonders to appear (mixed together, not seperately). I will call this the item list. Some common sense is in order here, you put the weakest units first and library must come before university etc.
Through a process of using search and replace in MS-Word and a lookup table in MS-Excel I have managed to extract a list of standard city improvements and wonders. Suffice to say, you may simply copy the list at the bottom of this page to a spreadsheet of your own.
Conecting the Dots
Now its time to create a series of techs next to your list of items. Depending on the scenario, you might want to name the items now and choose tech names which match or if you are portraying a well defined universe, you can name the techs first and choose the items accordingly. When you are done, you should have the basic framework of you scenario tree. The next step is to map each of the techs to an existing Civ2 tech slot.
This is the most difficult part as many advances have effects hard coded into them. Thus a familiarity with these effects is needed. There are many things you have to look out for, I will list the more important ones here.
Pop Up Message Advances
The discovery of certain advances leads to a pop up message.
- Fortress Message (allows fortresses to be built)
Explosives - Transform Message (allows terrain transformation)
Railroad - Railroad Message (allows building railroad)
Combined Arms - Paratrooper Message (none)
Refrigeration - Farmland Message (allows double irrigation with supermarket improvment)
Radio - Airport Message (Allows airlift and airfields)
Philosophy - Golden Age Message (free advance to first civ to discover)
The paratrooper message has no accompanying effect and can be used anywhere. If you do not have settlers you may change the Railroad, Explosives and Construction messages to suit your purposes. Sometimes you may already have some of the effects in place at the start so the messages are not relevant.
The discovery of certain advances leads to a new form of government. These are Monarchy, Fundamentalism(which also allows fanatics to be built), Democracy, The Republic and Communism (which also allows guerrillas to be generated automatically).
Gun Powder is the trigger advance which disallows the construction of units with the same role as the unit in the musketeer slot and with inferior attack/defence factors than the musketeer unit. I strongly suggest you either do not use the gun powder tech or do not use the musketeer unit slot. (the Knight slot has a similar effect but I have not been able to isolate the trigger advance).
Happiness Related Advances
Several Advances are related to the effcts of 'happiness' improvements:
- this must be made the prerequisite of the temple or your temples
will be disfunctional
Mysticism - increases effect of temples by 1
Monotheism - this must be made the prerequisite of the cathedral or your cathedrals will be disfunctional. Same applies to the Michelangelo wonder.
Theology - increases effectivenss of cathedrals by 1
Electronics - increases the effect of collosseums by 1.
Communism - decreases the effect of colloseums by 1.
Democracy - Courthouse makes one citizen content
The barbarian thing is a very complicated affair and very difficult to control properly. According to Willaim Keenan, one of the foremost experts on Civ2 scenarios, to limit barbarians to the Archer, Fanatic, Partisan, Rifleman, Horseman and Chariot slots you need to
Give Conscription, Guerrilla
Warfare and Mobile Warfare to at least one tribe at the start
Eliminate Iron-working and Gunpowder from your tree.
Please refer to Keenan's Barbarian Paper for a detailed explanation.
Miscellaneous Advance Effects
Some other effect are:
- nuclear plants are meltdown free, ships move 25% more.
Guerrilla Warfare - increases the number of guerrillas generated by Communism
Gun Powder and Mobile Warfare - sells barracks.
Map Making - tribes can exchange maps
Nuclear Fission - allows nukes to be built (with Manhattan Wonder), Uranium appears as trade item
Nuclear Power - ships have movement increased by 1
Trade - allows trading.
Automobile and Electronics together - change the city style to modern
There are many other minor
effects of advances, too many to list them here. Some effect which
city icons are used, pollution, demographics for calculating
civilisation rankings etc. Many people have written detailed accounts
of these effects, refer to their articles for detailed information.
With this information in mind, you should either pre-assign these special advances to a certain part of the tree or mark the as 'not to be used'. It will be very tedious to change the tree after you begin testing and find an undesirable effect. Beleive me.
One important thing to make sure is that each advance leads to at least one new unit, improvement or wonder. Nothing is more irritating than researching something only to find out it is useless (even if it leads to another advance). Another thing to ensure is that the prerequsite of each advance is one or two advances which lie above in the list. When you have the full version of your tech tree spreadsheet up, like the example I have iven below, you can check for these things.
This is part of the tree spreadsheet I used in making my Zweiter WeltKrieg scenario.
Implementing your Tree
Up till now, you have actually not physically changed anything in your scenario folder. But if you have dealt with all the different aspects mentioned earlier, you many begin with the customization. When you implement your custom tree you must do the prerequisites in one go. That is because the game will crash if there isn't a continuous line traceable from nil to future tech. (Alternatively, you may temporarily make the prerequisite of Future Tech to nil). You can do this by editing the rules.txt manually or use the in-built Advances editor. Start with the earliest techs and work your way down.
If you have more than one playable race, you may have planned tribe specific branches in your tree. The way to do this is to start with an unavailable advance with prerequisites of No No. The unavailable advance should lead to an innate advance which is then given via the cheat menu to the tribe it is meant for. My typical design has a main tree available to all and (three) other separate branches of advances which have one prerequisite from the main tree and a second prerequisite from the tribe specific branch.
Once there is a No No advance, you must remember never to use the in-built Advances editor as it will change all advances linked to the unavailable advance to No No advances. Another thing to watch out for is the Civ2 memory bug. Do not use any other in-built editor after using the Advances editor in the same session. You need to save (not as a scenario, just a normal save game) and reload.
After the tree is set up in its entirety, rename the units, improvements and wonders accordingly and you're well on your way to the completion of your scenario.
LIST OF IMPROVEMENTS AND WONDERS
SAM Missile Battery
Sun Tzu's War Academy
King Richard's Crusade
Marco Polo's Embassy
J. S. Bach's Cathedral
Isaac Newton's College
Adam Smith's Trading Co.
Statue of Liberty
Cure for Cancer
LIST OF ADVANCES