There are two battle modes. "Campaign" (a story mode) and "Attack A Rival Player" (Player versus Player / PVP).
The Campaign consists of a number of preset scenarios against predefined bases with special story objectives and the player is rewarded for certain steps of his progress with special crystals.
The Attack A Rival Player (PvP Mode) allows the player to start searching for other player bases to attack for resources, experience and medals. There are many Battle Zones depends of the level of the Scanner.
Winning against player in lower ranking Battle Zone will only give smaller amount of Energon and Alloy while losing will risking large amount of your Medal.
Winning against player in higher ranking Battle Zone will give big amount of Energon and Alloy and Medals while losing will risking only small amount of your Medal.
The enemy is choosen base on your medals ranking and the resource that are in the limit of the Battle Zone. **Assumption**
Alliance War allow your alliance to do war between alliance and get large amount of Resources base on your Alliance League level.
Events Battle Zones are battle zone that are created especially for the event battle only. Usually have different requirements and rewards and automatically open all zone no matter what level is your Scanner.