Parasitic wasps are extremely varied in their habits. Many lay their eggs in inert stages of their host (egg or pupa). If the prey is a caterpillar, they paralyze it by injecting it with venom through their ovipositor. Then they insert one or more eggs into the host or deposit them upon the host externally. The host remains alive until the parasitoid larvae are mature, dying later when the parasitoids pupate, or when they emerge as adults. Basically, the hosts are eaten alive.