Features of the game

• Place towers to destroy the goblins

• Upgrade towers to get even more powerful

• Sell towers to place even better towers

• Different types of goblins to make the game a little harder

Controls

• Press 'R' on the keyboard to toggle visibillity of the towers range
  
• Right click on the mouse to sell towers at half the price
  
• Left click existing towers to upgrade - An upgrade is successful if the range indicator turns orange it cost twice as much as the base price of the towers