Nessus is a centaur. Like the rest of his kind, he has the upper torso of a man stuck on to the body of a horse. The Greeks thought that most centaurs were wild savages. Nessus lives up to this reputation when he tries to force himself on Heracles' third wife, Deianira. For this crime, Heracles kills Nessus with an arrow poisoned with Hydra venom. In the end, however, Nessus shows that he's not just any stupid old centaur. By tricking Deianira into thinking that his poisoned blood is a love potion, Nessus ends up causing the death of Heracles.