These are groups of players who band together under a single banner, or “Tag” as it is called in the game (a tag is a short-hand abbreviation of an alliance name). Alliance members work together to improve their gaming experience through Trade, War, or Diplomacy.
The number of members in an alliance can be seen when you search for that alliance in Statistics, check the alliance’s information page or on the alliance overview if you’re an active member of that alliance. Members in alliances are assigned ranks with various privileges, as established by the alliance leadership.
Alliance members communicate using Forums, Alliance Circular Messages, or third-party chat applications agreed upon by the members.
A player may apply to join any alliance that is currently accepting applications. Some alliances post recruiting messages in the game Forum. You can also search for an alliance to join by tapping Alliance in the Main Menu. You can search for an alliance by the Alliance Name or its “Tag”, then tap the desired alliance name to visit their Alliance Page. The alliance information page is maintained by the alliance. If the alliance is accepting new members, an application link will be available.
Experienced players can start, or “Found” a new alliance (new players cannot create alliances). The Founder is the owner of an alliance. Founders have all rights in the alliance and cannot be kicked from the alliance. Other members may be granted administrator privileges by the Founder, allowing them to manage various alliance functions (managing the alliance home page and other settings, approving new member applications, etc.). To transfer Founder rank, the potential new owner must first have “Right Hand” privileges granted him by the current Founder.
Two or more Alliances may also choose to band together (temporarily or for an extended period), cooperating in diplomacy and trade, for military support or other actions. Perhaps the simplest form of cooperation between alliances is a Non-Aggression Pact, or “NAP”. This is a simple agreement between two alliances that their members will not attack each other. Alliances with a NAP agreement should clearly state this on their public alliance page and make their members aware of it.
An alliance may declare war on another alliance. Generally speaking, a declared war will remove the bashing restrictions between all members of the warring alliances, allowing unlimited attacks until the war is over. (See the Official Rules for the current policy on Alliance Wars and Bashing).