The Crystalline Entity is a mysterious space-dwelling lifeform that appears in Star Trek: The Next Generation. Next to nothing is known about its exact nature or if it is even sentient, but it has the appearance of a giant crystalline tree or, as others have described it, a giant snowflake. The entity feeds on vast quantities of organic matter and is responsible for stripping several inhabited planets of life, leaving nothing - not even bacteria - behind. One such planet destroyed by this creature was Omicron Theta, the place where the android Data was created.
Death[]
In the fifth season episode "Silicon Avatar", the Crystalline Entity attacks the planet Melona IV where humans have just begun establishing a colony. Most of the settlers survive by taking shelter in a cavern where the rocks are laced with deposits of ores that the entity's beams cannot penetrate. During the episode, the USS Enterprise-D follows the entity's flight path in order to study it and possibly communicate with it. However, Dr. Kila Marr - a human xenologist who had been studying the entity's activities for several years - interfered with the Enterprise's communication attempts by transmitting a consistent graviton beam toward the entity. The beam caused the Crystalline Entity to vibrate intensely until it shattered like glass.