Bills

Bills is the premium game resource.

What are the Bills for? How to get Bills?
 * For quickening the game processes;
 * For buying gold, wood. Iron and oil.
 * For momentary construction of buildings.
 * For byuing Chests with Mercenaries and Medals.
 * Buy in the Shop.
 * Buy in the Shop Free.
 * Complete tasks and earn achievements.
 * Invite your Facebook friends to the game.
 * Complete daily game tasks.
 * Win the Tournaments.
 * Eliminate Mercenaries that attack your Base and collect Bills from monuments they leave.