Minefield

Minefields are one of the favorite supports of the army of the machines, but occasionally you can acquire them yourself (for example, they are a reward for completing the Frozen Stone Foothills zone). When a minefield is dropped, it plants a pattern of 7 mines on the battlefield. If any unit (yours or the enemy's) passes near a mine, it will explode, doing significant damage to all nearby units. They do not have any placement restrictions, so you can drop them directly on your enemy's spawn point and enjoy the carnage.