Late game oil costs are an subject that's come up in a number of separate threads. To me, these requirements seem like a significant design issue and one meriting a more focused discussion. Below, I describe both what I perceive as the problem and how I'd go about resolving it. I'd welcome discussion of either. As one plays through the late game in GS, it becomes apparent that virtually every unit needs oil. Oil certainly is important in modern warfare (as well as many currently unrepresented civilian contexts), but I think the current representation is a bit off, in terms of both the impacts and the precise units involved. An infantry unit may use oil for transportation at times, but it clearly isn't dependent on it in the same way as a tank division or bomber squadron. Additionally, while a tank uses far more oil than a car, issues of scale mean that, on the whole, civilian uses consume far more oil (and produce far more CO2 emissions) than military ones. In GS, however, even a mid sized military can easily match a civ's industrial resource consumption. Things get even odder when you realize that advanced aircraft are among the few units that don't consume oil. This means that if you want a modern army but either lack oil or want to minimize climate change, you're better off flying warplanes across the world than garrisoning foot soldiers with guns in your cities. To alleviate these issues, which I think would improve both gameplay and realism, I'd propose two broad changes to the system of late game resource requirements: 1. Infantry and Artillery do not use oil. This ensures that any civ with appropriate tech and production can build an army with modern combat strengths (not made entirely from machine guns and anti-tank weapons), regardless of resource availability/choices. Such an army, would, however, suffer highly on the mobility front compared to an oil based one. Artillery and Anti-Tank could perhaps require niter if there's a desire for scale back slightly on the resource independence. 2. Vehicle based units consume iron (ships/tanks) or aluminum (aircraft) up front but have oil (coal for industrial ships) maintenance costs. However, they only incur these costs when actually moving. This change would have two benefits. First, it would prevent inactive military hardware from being the primary driver of climate change. Second, it would create a situation where civs can save up oil in peace but gradually draw down their stockpiles in protracted wars.