Destroy the enemy's boss tank to advance to the next level. The more enemies you destroy, the more money and points you earn for upgrades and improvement of your rank.
Shoot the enemies with a pistol or a sniper rifle. Don't let any get away as you move to
new levels. Mouse to aim and shoot. 1-3 switch weapon and R to reload.
Save the rebel fortress from a never-ending onslaught of enemy troops, jeeps, tanks, artillery and helicopters. Shoot them all down before they destroy it.
Your goal in this defense game based on StarCraft is to play as the Zerg Overmind and build up your defense and survive the combined Terran and Protoss attacks.