Aegisthus ambushes and kills Agamemnon in a feasting hall under the pretense of holding a feast in honor of Agamemnon's return home from Troy. Clytemnestra also kills Cassandra. Her jealousy of Cassandra, and her wrath at the sacrifice of Iphigenia and at Agamemnon's having gone to war over Helen of Troy, are said to be the motives for her crime. Aegisthus and Clytemnestra then rule Agamemnon's kingdom for a time, Aegisthus claiming his right of revenge for Atreus's crimes against Thyestes (Thyestes then crying out "thus perish all the race of Pleisthenes!", thus explaining Aegisthus' action as justified by his father's curse). Agamemnon's son Orestes later avenges his father's murder, with the help or encouragement of his sister Electra, by murdering Aegisthus and Clytemnestra (his own mother), thereby inciting the wrath of the Erinyes (English: the Furies), winged goddesses who track down wrongdoers with their hounds' noses and drive them to insanity. The Curse of the House of Atreus Agamemnon's family history is rife with misfortune, born from several curses contributing to the miasma around the family. The curse begins with Agamemnon's great-grandfather Tantalus, who is in Zeus's favor until he tries to feed his son Pelops to the gods in order to test their omniscience, as well as stealing some ambrosia and nectar. Tantalus is then banished to the underworld, where he stands in a pool of water that evaporates every time he reaches down to drink, and above him is a fruit tree whose branches are blown just out of reach by the wind whenever he reaches for the fruit. This begins the cursed house of Atreus, and his descendants would face similar or worse fates. Later, using his relationship with Poseidon, Pelops convinces the god to grant him a chariot so he may beat Oenomaus, king of Pisa, in a race, and win the hand of his daughter Hippodamia. Myrtilus, who in some accounts helps Pelops win his chariot race, attempts to lie with Pelops's new bride Hippodamia. In anger, Pelops throws Myrtilus off a cliff, but not before Myrtilus curses Pelops and his entire line. Pelops and Hippodamia have many children, including Atreus and Thyestes, who are said to have murdered their half-brother Chrysippus. Pelops banishes Atreus and Thyestes to Mycanae, where Atreus becomes king. Thyestes later conspires with Atreus's wife, Aerope, to supplant Atreus, but they are unsuccessful. Atreus then kills Thyestes' son and cooks