Wilds

Wilds can be seen all over the map and includes: Grassland, Plain, Hills, Mountain, Oil Field and River.

All the wilds gives a bonus to your resource production except Plain. Plain are used for building extra cities, otherwise, they are pretty useless. Other Wilds cannot have cities constructed on them.

The bonus that Wilds provide increases with their Lvls, and also becomes harder to conquer, as the number of defenders increases with each Lvl.

The bonuses that each wild provides is listed below:
 * Grassland - Food
 * Hills - Stone
 * Mountain - Steel
 * Oil Field - Oil
 * River - Food
 * Plain - None (can be used to build cities)

Note: Wastelands are "quoting Global Warfare - ...impenetrable, and cannot be attacked."