History:
A massive spaceborne single-celled organism that consumed the Gamma 7A System and the U.S.S. Intrepid in 2268. The creature strongly resembled microscopic protozoans found on terrestial planets, save for its enormous size. The spaceborne amoeba was some 18,00 kilometers long, and about 3,00 kilometers wide, surrounded by a large energy-absorbing field. The creature was believed to originate from outside our galaxy. The Starship Enterprise approached the organism shortly after stardate 4307 and was nearly crippled by the amoeba's energy-absorbing field, termed a "zone of darkness." The organism was destroyed by an antimatter bomb planted into the amoeba's nucleus with assistance from a shuttlecraft piloted by Spock.
TOS "The Immunity Syndrome" ; Star Trek Encyclopedia II
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