Orbalisk
this barnacle-like creature lived on the moon Dxun. These symbiotic parasites were protected by a hard shell, and oozed an acidic slime that they used to eat away at whatever surface they attached themselves to. Orbalisks preferred to feed on living flesh, and could infest a living sentient in minutes. These creatures were attuned to the Dark Side of the Force, having lived in proximity to Exar Kun's tomb for many millennia. Because of this, any orbalisk which attached itself to a Sith Lord or other Dark Side adept would form a mutually beneficial symbiosis. Many Sith warriors chose to use orbalisks to create a kind of living armor which grew as the orbalisk reproduced. The individual orbalisks had to be removed, or the being would be covered and consumed by the orbalisk family. However, once a stable, symbiotic relationship was established, the orbalisk armor actually helped heal wounds which its host suffered.