at last one plan seemed best:
he would send a murderous dream to Agamemnon.
…"Zeus commands you to arm your long-hatred Achaeans,
to attack at once, full force –
now you can take the broad streets of Troy!"

– Homer

The Iliad, Book 2, lines 5-7, 33-34. Zeus gives a false steer to Agamemnon in his war with the Trojans, by sending a fraudulent dream of hope commanding him to attack Troy immediately. The king of the gods is fulfilling his promise to Thetis to help the Trojans. This interference by the gods in human affairs is an example of dramatic irony. Agamemnon is convinced by Zeus that his army is about to inflict defeat on the Trojans, but the reader knows that the Trojans will be able to inflict terrible damage in this full-on attack.