Kid Dinosaur

Kid Dinosaur was a fictional character from the Wild Cards anthology series, and was created by Lewis Shiner.

Arnie Fentner was a normal kid, obsessed with Dinosaurs and comic books, just on the cusp of puberty, when the dormant Wild Card virus he'd inherited from his mother turned active, altering his DNA and restucturing his body. He was one of the lucky few who didn't die, and one of the one percent who gained superhuman abilities as a result; in his case, the power to restructure the molecules of his body to assume the shape of any Dinosaur that he knew about. The downside was that his body's mass remained constant, so he could only become a kid-sized version of a "Tyrannosaurus rex", "Pteranodon", or a "Triceratops", not to mention the fact that he would burst out of his clothes when transforming, leaving him naked and vulnerable to the elements when he returned to normal. Still, it gave him what he'd always dreamed of: the chance to take part in the adventures of Aces, often playing hooky from school to trail prominent Aces with little regard for his own safety.

This devil-may-care attitude would be his downfall; on one of his excursions, the Kid was captured by the Astronomer and his minions, to be used a human sacrifice intended to forcibly induct the Ace Water Lily into their cabal. Arnie and Water Lily were ultimately rescued by the impromptu group of Aces organized by Fortunato and Dr. Tachyon to rout the Astronomer's group from their headquarters in the Cloisters. The Astronomer marked all those who'd humiliated him for death, and on Wild Card Day (September 15), 1986, the Astronomer tracked down Arnie in a crowd at Jetboy's Tomb, and, as Fortunato watched helplessly, the old man tore Arnie's heart out.

In answer to protests from loyal fans of the character, Wild Cards series editor George R. R. Martin noted in his afterword to the 2004 edition of "Jokers Wild" (the novel where Kid Dinosaur's death was depicted) that the Kid was created specifically to be a victim of the Astronomer's vengeance.