If all of your ships are destroyed the game ends. Use the mouse to aim where to shoot then click the left mouse button to fire. Hold the mouse button down for auto-fire . A set of ships are provided at the start of the game. Additional ships with increased power will arrive in subsequent missions.
All ships have a hull rating.
Some ships are also equipped with shields. Damage is first inflicted on the shields. Once the shields are down damage is then inflicted on the hull. When the hull is knocked out the ship is destroyed. At the end of each mission all ships perform auto-repairs which provides upto a fifty percent repair in both shields and hull.