Medea and The Marathonian Bull, Androgeus and The Pallantides
When Theseus arrived at Athens, he did not reveal his true identity immediately. Aegeus gave him hospitality but was suspicious of the young, powerful stranger's intentions. Aegeus's wife Medea recognized Theseus immediately as Aegeus' son and worried that Theseus would be chosen as heir to Aegeus' kingdom instead of her son Medus. She tried to arrange to have Theseus killed by asking him to capture the Marathonian Bull, an emblem of Cretan power.
On the way to Marathon, Theseus took shelter from a storm in the hut of an ancient woman named Hecale. She swore to make a sacrifice to Zeus if Theseus were successful in capturing the bull. Theseus did capture the bull, but when he returned to Hecale's hut, she was dead. In her honor Theseus gave her name to one of the demes of Attica, making its inhabitants in a sense her adopted children.
When Theseus returned victorious to Athens, where he sacrificed the Bull, Medea tried to poison him. At the last second, Aegeus recognized the sandals, shield, and sword, and knocked the poisoned wine cup from Theseus's hand. Thus father and son were reunited, and Medea, it was said, fled to Asia.
When Theseus appeared in the town, his reputation had preceded him, having travelled along the notorious coastal road from Troezen and slain some of the most feared bandits there. It was not long before the Pallantides' hopes of succeeding the apparently childless Aegeus would be lost if they did not get rid of Theseus (the Pallantides were the sons of Pallas and nephews of King Aegeus, who were then living at the royal court in the sanctuary of Delphic Apollo). So they set a trap for him. One band of them would march on the town from one side while another lay in wait near a place called Gargettus in ambush. The plan was that after Theseus, Aegeus, and the palace guards had been forced out the front, the other half would surprise them from behind. However, Theseus was not fooled. Informed of the plan by a herald named Leos, he crept out of the city at midnight and surprised the Pallantides. "Theseus then fell suddenly upon the party lying in ambush, and slew them all. Thereupon the party with Pallas dispersed," Plutarch reported.
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