Hey everyone, This is an idea I have had for a while, and I would like to hear what you think of it. One major factor that facilitated the European conquest of the new world was disease. Tens (maybe hundreds) of millions of natives were killed over the centuries by diseases like smallpox, measles, plague, typhoid fever, etc. In fact, many more natives were killed by disease than by violence. Apart from that, there have been some severe epidemics in European colonies as well: http://en.wikipedia.org/wiki/Disease_in_colonial_America#Epidemic_of_Diseases I've always felt this should be included in the game in some manner. We now have the relatively new feature of Health, and one event about diseases in native villages. I have some general ideas how I would like disease to function in the game. I do not know how much programming work these would require, and maybe some of them are technically impossible. This is a kind of brainstorm. Concept: Spreading diseases: Diseases can be spread by all units except for sea animals. A unit can infect other units in the same tile or adjacent tiles, or settlements in these tiles, there is a random chance this will happen. Diseases start in Europe, and are brought to the New World by ships sailing back and forth. Infected units: When a unit becomes infected, it will take a few turns before the disease becomes apparent, and the unit becomes ill. When that happens, the player receives a message, so before that time, the player does not know that a unit is infected. That is very important, otherwise it would be much too easy for the player to fight a disease (it is also more realistic, of course). That unit receives a random amount of damage every turn for a few turns, after which the disease fades, and the unit is healthy again. It it also possible that a unit is a carrier. In that case, it never gets ill itself, but it retains the possibility to infect other units or settlements. Non-human units (wagon trains, siege weapons, animals) can only be carriers. For infected human units, there simply is a certain probability that they get ill after infection. Infected settlements: If a settlement becomes infected, an epidemic occurs. The practical effect of this is that a lot of negative Health is added each turn during an epidemic, which causes the Settlement Health to plummet rapidly. In the case of an epidemic, the Settlement Health gets a new, lower minimum, to reflect the complete stagnation of daily life and productivity that happens in such periods. If an epidemic is severe enough, colonists may die. The negative health threshold beneath which a particular kind of colonist is in danger can vary. The probability that a colony gets hit by an epidemic is also dependent on the initial Health of that colony. It would also be nice to have some kind of visual effect for settlements experiencing an epidemic, comparable to the smoke and flames you see when there is civil unrest. Maybe green smoke or something. Differences between natives and Europeans: Obviously, natives should be more affected by diseases than Europeans. In colonial history, Europeans could get weakened by epidemics and suffer economic setbacks, but the natives were hit much harder, and lost large parts of their population. This could be reflected by giving natives a much higher vulnerability to diseases (a numeric value that could be coded in XML). As a result of this, an epidemic would kill a significant part of the population of a native settlement, or kill off infected braves. In contrast, the death of colonists or units among Europeans should be much rarer, and happen only during the severest epidemics, if the player fails to take proper precautions, or if units are already weakened by battle. Also, the native units of human players, (slaves, converts and mercenaries) should be just as vulnerable as other natives. Among these three, slaves should be the most vulnerable, as disease was historically one of the main reasons the colonial powers eventually went to Africa for slaves, and they live in far worse conditions than converts or mercenaries. This could be compensated by reducing the chance native slaves run away. That way, the biggest disadvantage of African slaves is that they can run away, while the biggest disadvantage of native slaves is that they often die of diseases. Balancing for the negative effects on native tribes: Because natives will be harder hit, this would make it too easy to wipe them out early in the game (although that would be realistic). So to compensate for this, natives ought to start much stronger. That is something that I would like anyway, as currently, when you arrive in the New World, there are very few natives, and it is clear they are only just starting up as well. I don't know if it is possible, but I would like it to let natives grow and develop for a while before Europeans arrive. For example, if, at the beginning of each game, the natives get 50 turns on autoplay to build up and develop themselves, they would be stronger and more populous, and the player would have much more the impression of arriving in societies that are already functioning. But I don't know if that is technically possible. Also, natives will gain the ability to generate Health in their settlements as well. Negative health will only happen to them during an epidemic though. The role of Health in diseases: There are several ways to fight diseases, and Health is the most important. A settlement with positive Health has a lower risk of epidemics. If an epidemic occurs, this would also mean that more Healers need to be employed. I would also really like that, as currently, you seldom need more than one Renowned Medic to keep a large city healthy. I've also come across nice building art for a Plague Hospital, but I cannot find it back at the moment. But I would like to include it, either as a building where extra healers can work during an epidemic, as a building without workers that just reduces the negative health generated by the epidemic, or, which I would like best, a building where you can put sick colonists in "quarantine," so they cannot spread the disease further. Immunity: Units that became ill and recovered will be less strongly affected during the next epidemic, or do not become sick of all and can only be carriers. Occurrence and duration of epidemics: The game should obviously not become a ceaseless string of epidemics. They should occur only once in a while, and just as sick units will recover after a few turns, an epidemic in a settlement should not last too long either. Additionally, units and settlements should be completely immune for a while after recovery, otherwise an epidemic could last indefinitely. For example, it would be nice if once in 40 years an epidemic occurs, which lasts four years. That way, 90% of the time your colonies would still function normally. Epidemics could also vary in severity. For example, numerous mild epidemics that kill a few natives and mildly affect a few colonies, and a few severe ones that ravage the natives, stifle your economy and kill a few colonists. Why I would like this feature: Because it would offer the player many really interesting gameplay choices. Stagnation of trade and transport: If an epidemic occurs, the player has to make harsh choices. Units that constantly travel between settlements are the most likely to spread the disease: transport units and ships. The player can leave his colonies running their normal routine and risk a pandemic, or he can stop transport to and from infected cities, and suffer economic damage. Perhaps an easy "quarantine" function would then need to be added to the trading system. Once it is activated by the player, all automated trade to and from that settlement is halted, and automated units will not enter the plot of that city. When the epidemic is over, the quarantine is lifted automatically. Biological warfare: There are some dubious claims made about colonists in history deliberately infecting natives with infectious diseases. While these are disputable, it certainly would become possible with this feature to use disease to your advantage. Maybe the spread of diseases should negatively affect your relationship with affected native tribes as well. Employing more healers (more dynamic): I like the addition of Healers and Health, but I think it currently functions in a relatively simple and static way that is completely controlled by the player. With the disease feature, the player would suddenly need to employ more healers during epidemics, taking workers off the fields to help caring for the sick. Health would also limit the ability of a disease to gain a foothold and spread. Tackling a crisis, solving puzzles: One thing I already know I would really like is to trace back a disease, and find out where it started. Because a unit can infect other units before he becomes ill himself, you have to trace back the movements of a unit the past few turns, and find out what other units or settlements might be infected, and might spread the disease further. That is nice for players who like a bit of puzzling. More realism: As I mentioned before, disease played a very important role in this part of history. I welcome all ideas, suggestions, criticism and other kinds of feedback. Especially on the technical possibility of this feature, as I do not know very much about that myself.