Defender's Quest is an RPG-inspired tower defense game with a storyline. Protect the main character from hordes of nasty creatures by summoning melee and ranged defenders. Summoning and upgrading defenders requires PSI energy, which you'll gain each time an enemy is killed. In addition to summoning units and boosting their abilities, you can cast spells with your energy. You will gain gold and your characters will gain experience points when you win a battle. Winning a battle will also unlock new stages and towns. Make sure that you visit these towns to buy items and hire defenders. Each defender can be equipped with your acquired items and upgraded (if they have skill points).