Hollow Fly is an action-adventure game where you have to collect all the keys in a level in order to open the portal and go to the next level. You will find many enemies and hazards on your way to the light. You will face 3 maze-like worlds. You can defeat your enemies with your powerful sonar beam. Collect different power-ups to increase your speed, your fire power or your health, but if you lose a life you will lost all your power-ups too.