Resource management in Empire Earth 2 is quite similar to what you might have seen in the first Empire Earth.
Main resources[edit]
There are four main resources, that were already present in EE1. Namely, those are Wood, Food, Gold and Stone. Wood and Stone are mostly used to build new structures (defensive buildings usually require more Stone than Wood), while Food and Gold are used to hire new units.
Wood[edit]
Food[edit]
Gold[edit]
Stone[edit]
Wood and Stone are mostly used to build new structures (defensive buildings usually require more Stone than Wood), while Food and Gold are used to hire new units.
Special resources[edit]
In addition to the four main resources, different special resources may be found and gathered. There are two special resources usable in a given era. Special resources are rarer than main resources and are specific to certain epochs. If you play a multiplayer game, depending on the beginning and final era you chose, gathering special resources might be a complete waste of time (Tin is for example pretty useless once you reach the 5th epoch). But since this guide attempts to cover the single player campaigns, let's say that you'll have to gather a lot of special resources, and that many levels will revolve around them.
Hopefully, most single player scenarios only cover one or two epochs, so you won't have to worry about your special resources becoming useless later on.
Here is a list of special resources, with their respective epochs:
- Tin (From Epoch 1 to Epoch 6)
- Iron (From Epoch 4 to Epoch 9)
- Saltpeter (From Epoch 7 to Epoch 12)
- Oil (From Epoch 10 to Epoch 15)
- Uranium (From Epoch 13 to Epoch 15)
Special resources are mostly used to hire and upgrade units.
Tin[edit]
Iron[edit]
Saltpeter[edit]
Oil[edit]
Oil is a special resource available from Epoch 10 (the Industrial Age) to Epoch 15 (the Synthetic Age).
Oil is gathered by building Oil Derricks on an Oil Deposit. You can garrison up to six Citizens inside a Derrick. The more Citizens garrisoned, the faster you gain Oil. The gathering rate is increased by your Territory's bonii, but not by your Warehouses' ones.
Uranium[edit]
Uranium(
) is a special resource available from Epoch 13 (the Digital Age) to Epoch 15 (the Synthetic Age).
Just like Oil, Uranium is gathered not directly by your Citizens but by a building: the Uranium Mine. You can garrison up to six Citizens inside a Mine. Obviously, six citizens will gather Uranium faster than one or two. The rate at which you gain Uranium is increased by your territory bonii (Resources Dropoff Bonus).
The art of resource gathering[edit]
Gathering resources in EE2 is overall pretty straightforward: you hire peasants and 
on the resource spot. The peasants will start gathering resources and then stock them in your City Hall or in a Warehouse.
Exceptions to this are the Oil and the Uranium special resources. To gather Oil, a player will have to build an Oil Derrick on an Oil Deposit, while building a Uranium Mine lets the player gather Uranium.
In order to maximize resource gathering, it is advised to have at least six peasants on a resource deposit. Having more than eight is usually a waste, and may create pathfinding issues.
A difference from EE1 is that (most) deposits offer infinite resources. There are a few exceptions, such as hunted animals or trees, but even then, you'll never run short of Wood or Food as long as you have enough gatherers.
Depending on the level, you'll need more of one kind of resources than others. In defensive levels, you'll likely require more Stone than usual (to build and repair fortifications), while sea battles will put a strain on your Wood gatherers. All this is pretty common sense if you've already played Age of Empire or any similar game.
Maximizing your Production: Warehouses and City Centers[edit]
Just as in Empire Earth 1, you can increase your production in EE2 by putting citizens into a stockage building. Each peasant working in a Warehouse or in a City Center increase the amount of resources delivered in the building by 2%.
At the beginning of the game, you will only be able to put five peasants into a storing building (which already increase its production by 10%), but this number soon enough increases to 10, and 15.
Note that this production bonus only comes into effect for the resources that your peasants will drop into this very building. Note also that the peasants you put into a storing building do not disappear and thus still take up unit slots. Finally, note that you can ask them to leave the building if you want.
That being said, it is not always a good idea to put workers into a storing building. First, you'll often be short on peasants anyway. They die easily and are somewhat long to hire. Second, you'll often also be short on housing, and wasting 15 population slots is sometimes not a very good idea.
You should you fill Warehouses with citizens when a building is used to store three or more different resources. If you have around 20 workers using a same Warehouse, then increasing its productivity is a must.