Your mission in this cool strategy game is to lead savage horde of rabid aliens and invade the Earth annihilating all the major earth cities. But be aware, the humans will resist. Kill human units to gain evolution points and use them to buy or upgrade your units. Go through multiple levels and use various combinations of units and upgrades to achieve victory. Use WASD or ARROW KEYS to move. Press "Q" or "E" KEY to select unit to spawn. Press the SPACEBAR to spawn an alien. Good luck!