The D-Rex, or Distortus rex, is a mutant dinosaur created by InGen. Bred from the modified DNA of a Tyrannosaurus rex and other species, the D-Rex was one of many failed attempts at creating a larger, more intimidating hybrid. The specific D-Rex seen in the film is grotesquely deformed, possessing six limbs, a stunted tail, and an enlarged, soft skull that suggests a reduced intellect and dulled senses. It hunts at night, using its keen sense of smell and hearing to ambush its prey, and has opposable thumbs on its ape-like forelimbs. The D-Rex is portrayed as a tragic creature that has lived in constant agony due to its genetic mutations, and unlike other hybrid villains in the franchise, it was never killed.
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