Your base has been attacked by Korn Corp invaders and it's time to summon all your forces to defend you land. Build defenses to kill incoming waves of enemies. Build barracks, air defense system and defense turrets to slow down the enemy. Place your units strategically in Colony Defenders TD game to destroy your enemies. Instructions: Use command center to construct buildings. Use Defensive buildings to create different units. After creating your units click on start button at the bottom of the screen.