Evil scientist Dr. Gero created the Androids for his own nefarious purposes. In an attempt to defeat the Z Warriors and destroy the Earth, Dr. Gero even goes so far as to turn himself into an Android.
Android 16
Big and powerful, Android 16 prefers to let his muscles do the talking for him. Android 16 joins 18 in the fight against Cell.
Android 17
Android 17 is a dark-haired youth with a major attitude problem. He later contributes to the threat against Earth that forces Trunks to travel back in time.
Android 18
Android 17's "sister," the beautiful Android 18 has a real mean streak, but she does help our heroes make a final stand against the power-hungry Cell.
Android 19
The first Android to arrive on Earth, Android 19 is a clever, overweight warrior with a love for exotic weapons.
Android 20
In an attempt to become more powerful than ever, Dr. Gero commands Android 19 to turn him into Android 20. As an Android, Dr. Gero lets nothing get in his way.