Place units on the grassy areas to prevent invading animals from reaching your village. Enemies will travel by ground and air so be prepared for both threats. Some units need to be researched before they can be purchased. When you have enough gold, select the next darkened unit to research it. Place researchers on the map to discover areas with oil and fertile soil. Researchers occupy a tile temporarily and reveal a number (0-3). The number 0 indicates that the tile shouldn't be used to build an oil tower or granary. When placed on a tile with a number above 0, oil towers will produce money and granaries will produce food. Scroll the map with the left and right or A and D keys.