10 Creepiest Star Trek Aliens

10. Armus

As depicted in the Star Trek: The Next Generation episode Skin of Evil, Armus was a sentient smear of matter resembling an oil slick that could also take a vaguely humanoid form. In this form, it looked like a colonial mob was interrupted in the middle of tarring and feathering a tax collector.

Armus came into existence when the inhabitants of Vagra II purged themselves of negative emotions and, in a move that doesn't seem particularly responsible, just sort of let them coalesce into a disgusting puddle.

Armus was capable of projecting a force field that could block sensors, transporters, and communications. It could also project energy, use psychokinesis, and teleport people.

Armus caused the crash of an Enterprise-D shuttle and then waited for the rescuers to arrive so it could amuse itself by torturing them. Armus was fond of incorporating its victims into its liquid form and inflicting suffering.

When Enterprise chief of security Tasha Yar tried walking to the crashed shuttle to rescue its passengers, Armus murdered her with an energy blast just because he could.