Pillage is an player vs player option in which you battle against another player's deck as controlled by the computer. While your hero does not gain in the campaign, the hero may gain gold, runes, and experience points with victories.
Mission Pillage and Social PillageEdit
In the Missions option on the Main page, your hero may be challenged to Pillage any number of other heroes to receive a bonus when that number have been pillaged. A player will be chosen to Pillage, and you may change selection by paying 200 gold.
Under the Social option on the Main page, your hero may select Pillage but will be free to choose from a number of players against which to play. The targets to be pillaged are of the same level as your hero.
Note that your player may also be pillaged, in which case you will get a notice in your Social Inbox - either that you may avenge yourself, or take revenge.
The AI behind Pillage makes rather predictable, and sometimes less rational, moves when compared with a human player. This allows some advantage in being able to play against a stronger deck. For example, if a minion slot is occupied with an attacker, the AI may play a minion opposite an unoccupied slot, thus guaranteeing that the player's minion will strike the AI-controlled hero unopposed.