 A significant feature of the Genesis planet are the alien worms that rapidly evolve from microbes on Spock 's coffin . The creatures start as small , slimy crawlers , then grow to lengths of 8 feet ( 2 @.@ 4 m ) . The small worms were created by injecting molten " Hot @-@ Melt " vinyl into epoxy polymer molds that were immediately put into cold water to create a translucent product . The resulting hundred or so creatures were painted and coated with methacyl , a slippery , slimy coating . Each worm was attached to an elevated platform by a piece of fishing line ; the lines were tied to rods underneath the set . Offscreen helpers pushed the rods or pulled fishing line to create motion ; the scene required many takes because the fishing line would periodically flash at the camera . The larger worms proved more problematic , with filming taking place at ILM and Paramount Stage 15 . Similar to The Wrath of Khan 's parasitic Ceti eels , the worms featured cobra @-@ like cowls and a ringed mouth of teeth . ILM built one of the worms with more articulation than the others ; Ralston operated the creature through a hole in the set floor with his hand stuck inside the creature . The other worms were animated using pneumatic bladders that caused air to pass through hoses in sequence , creating an undulating motion . During the scene the worms attack Kruge , who kills one of them . The usual method for achieving the effect of the creature wrapping itself around Kruge would have been to film the sequence in reverse , but this posed problems : the slime coating Kruge would have been out of place with reverse filming , and multiple takes would ruin the Klingon makeup Lloyd wore . ILM 's solution involved rigging the worm with fishing lines that were pulled in a choreographed fashion by multiple off @-@ screen helpers to simulate the wrapping movement . When small pieces of the Klingon uniforms caught or snapped the fishing lines , Ralston resorted to steel cables . 
