Galdani

The Galdani are a highly advanced, ruthless space-traveling alien race. Their physical form is unknown, but on the outside they appear to be roughly the size of a human, but their bodies are encased from head to feet in a cylindrical armored shell, with just a letter box slot to see out of. They have no arms or visible legs in the human sense, but a single snaking trunk from the mid chest area ends in a huge claw which is capable of crushing a man's throat. The Galdani are discovered by Brigadier Lethbridge-Stewart and Dr Anne Travers, resting in cryo sleep inside their space ship, buried deep below the Australian Opal mining town of Coober Pedy. They are awakened by psychic energy harvested from hapless humans who have come into contact with their seductive, hallucinatory devices known as "dream eggs". As with the Malus home world Hakol (from the Fifth Doctor TV story The Awakening) the Galdani have learned how to harness mental energy the same way humans on Earth use electricity. The Galdani are merciless to humans whom they view as little more than cattle. (The Galdani appear in the Lethbridge-Stewart novel The New Unusual. They were created by Adrian Sherlock)