H is for Horta

The Horta was a silicon-based lifeform from Janus VI. It was composed of a material similar to fibrous asbestos.

Horta physiology was very different from the carbon-based norm more commonly found in the galaxy. Horta were difficult to detect with tricorders, and were invulnerable to type 1 phasers, though they could be injured with an adjusted type 2 phaser. They fed on rock, and thus they were nourished just by tunneling. Horta tunneled through rock like most humanoids walked through air, moving with the aid of an extremely corrosive acid. They left perfectly round tunnels in their wake. This acid was so corrosive that it only left fragments of bone and teeth if used on a Human. Although Hortas did not evolve in an oxygen environment, they seemed able to exist in it for extended periods of time.

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