Unidentified fog-like creature

A semi-sentient black fog–like creature was created by the Galactic Empire aboard the escort frigate–turned-laboratory Imperial Research Station 13 as part of experiments aiming to tap into the dark side of the Force. The entity consisted of a part of the essence of the dark side and possessed sentient beings, feeding upon their life force. After its creation, the creature proceeded to turn on the starship's crew, who all perished.

Eventually, at one point during the Galactic Civil War, the light freighter Sidewinder arrived near Imperial Research Station 13. The dark side creature used 3PO-series protocol droids and R2-series astromech droids to draw the freighter's occupants into the interior of the frigate. It then rushed toward the starship, possessing one of the newly arrived individuals, and attempted to use the ship to escape to a region of populated planets where it could feed on millions of sentient beings. However, before it could do so, the former occupants of the Sidewinder destroyed that vessel, sacrificing their own lives in order to strand the creature. It then went on to drain those individuals of their life force over a span of months before ultimately starving to death.

Text and facts from the “Unidentified fog-like creature” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.