Defender is an arcade game made by Williams Electronics in 1980. It is, essentially, a test to see how long you can stop aliens from overtaking Earth. You "defend" 10 humans from being mutated into aliens themselves. If you lose all of your humans, you enter "space," which is incredibly difficult to exit to get back to Earth. If you lose all your ships, you die, and Earth is defeated. Game Over.
Defender is played by pressing 5 separate buttons with unique actions and an up / down lever on an arcade control panel. One token is worth 3 ships and 3 Smart Bombs, and every 10,000 points awards one ship/Smart Bomb combo.
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