Hypnos can be said to be the god of hypnosis who enters the sleep of mortals and, at the bidding of the Olympians, gives them dreams of foolishness or inspiration, depending on the individual and their divine protectors or enemies.
Hypnos is husband to Aglia, one of the Graces, because he did a very dangerous favor for Hera. During the Trojan War, Hera wanted to distract Zeus from the battle so she could assist the Achaians, who seemed to be losing the war. She wanted Hypnos to cast a spell of sleep on Zeus but he refused. At first Hera offered Hypnos a golden throne crafted by her son Hephaistos but she was forced to raise the ante when Hypnos reminded her of the only time he had dared cast sleep on Zeus. Long before the Trojan War, Hera was angry with Herakles and she had persuaded Hypnos to make Zeus sleep while she tormented the hero. When Zeus awoke, he was in a rage. He searched for Hypnos and finally found him hiding in the arms of his mother, Night. Zeus swallowed his anger and warned Hypnos not to try it again, otherwise Hypnos went unpunished.
In preparation for this new deception, Hypnos made Hera swear oaths of her sincerity. He agreed to help her deceive Zeus for the hand of one of the Graces, Aglia (or Pasithea). He turned himself into a bird and, before Zeus could see him, hid in the tops of the trees on Mount Ida. He stayed hidden until Hera had seduced Zeus. When the father of gods and men was dulled by pleasure and sleep, Hypnos flew to Poseidon and urged him to increase his efforts in helping the Achaians because Zeus was asleep and unaware of the Earth Shaker’s meddling. Poseidon strode through the ranks of soldiers and urged them on. Finally, his bellowing and screeching roused Zeus from his slumber but, in that short time, the Achaians had turned the battle back on the Trojans. Hera’s trick had worked. Zeus never found out that Hypnos had betrayed him (again).