Laelaps

Laelaps was a Greek mythological dog who never failed to catch what he was hunting. He was a gift from Zeus to Europa. The hound was passed down to King Minos. Minos had been cursed by his wife; he ejaculated scorpions and spiders that would devour the genitals of those he slept with. Because of this, he called Procris of Athens to his aid. When she cured him he gave her Laelaps and a javelin that never missed its target. Procris's husband decided to use the hound to hunt the Teumessian fox, a fox that could never be caught. This was a paradox, a dog who always caught his prey and a fox that could never be caught. The chase went on for quite a while until Zeus turned both to stone, perplexed by their contradictory fates.