Back in the early 1990's during the massed alien "Invasion!" event, the Dominators wanted to experiment on the newly discovered human "metagene" and so put a number of humans through lethal training exercises. Most died, but a few survived, more than the statistics estimated should have, so the Dominators deduced that they were likely to be ones who were metagene active. And so tested them again, and so on...
Snapper was one of the final stage survivors, he discovered he could teleport vast distances easily by snapping his fingers, but he had to make sure he kept his eyes shut when he did so, because if he actually tried to see the place he was teleporting through it would leave him zoned out for a couple of weeks at a time.