Protect Zone

You, together with your troops are now in red alert. The lab was already been destroyed and the mutated species were all set loose! Now you and your troop must defend the base against those abominations in all cost. Do not let them go beyond the red line. Kill them before they got near it or else it's going to be hard for you to keep the base safe! Play Protect Zone now and see if how long you can hold the line!