Novelties introduced into traditional myths are an essential characteristic of Greek tragedy. Each and every play demonstrates, in different ways, how tragedians were versatile and innovative in handling mythic material. Modern prefaces to individual tragedies often discuss the possible innovations in the dramatization of a myth compared to previous or subsequent versions. Innovations advanced in a play sometimes became so familiar that they came to be regarded as ‘standard’. Such examples include the condemnation and death of the protagonist in Sophocles’ Antigone and, in all likelihood, Medea's filicide in Euripides’ Medea.